updated layout for webmail

internal/db/crud_mailbox_folders.go

@@ -1,18 +1,450 @@
 package db
 
-// CreateMailboxFolder records a custom folder's existence even before it holds any
-// messages — idempotent (a folder a filter rule already delivered into can be
-// explicitly created too, without erroring on the duplicate).
+import (
+	"database/sql"
+	"errors"
+	"sort"
+)
+
+// StandardMailboxFolders are the folders every mailbox always has, regardless of
+// whether they currently hold any mail — the single source of truth shared by the
+// webmail UI (which always shows them in the sidebar) and the IMAP LIST handler
+// (which must report them too, or a desktop client never learns Trash/Junk exist
+// until a message happens to land in one). These 5 are always top-level and never
+// renamed or reordered relative to each other — only custom folders nested under
+// INBOX (or, after being deleted, under Trash — see webmailDeleteFolder) form a real
+// tree; see the parent_id/parent_root doc comment on esrv_mailbox_folders.
+//
+// "Junk" (not "Spam") specifically because several desktop IMAP clients look for a
+// folder literally named "Junk" to auto-recognize it, even though the SPECIAL-USE
+// \Junk attribute (see specialUseAttrs, internal/imapserver) is supposed to make the
+// exact name irrelevant — in practice not every client honors SPECIAL-USE reliably.
+// See migrateSpamRenamedToJunk (schema.go) for existing mailboxes that already had a
+// "Spam" folder before this rename.
+var StandardMailboxFolders = []string{"INBOX", "Junk", "Sent", "Drafts", "Trash"}
+
+func isStandardFolderName(name string) bool {
+	for _, f := range StandardMailboxFolders {
+		if f == name {
+			return true
+		}
+	}
+	return false
+}
+
+// AllFoldersForMailbox is mailboxID's full folder list: the standard folders above,
+// plus every folder that either holds at least one message (DistinctFoldersForMailbox)
+// or was explicitly created and is still empty (ListMailboxFolders) — a folder can
+// exist via either path, sometimes both. This is a flat list (IMAP LIST, the "Move
+// to…" dropdown, and any other non-tree consumer) — for the sidebar's actual tree
+// structure, see FolderTree.
+func (d *DB) AllFoldersForMailbox(mailboxID int64) ([]string, error) {
+	fromMessages, err := d.DistinctFoldersForMailbox(mailboxID)
+	if err != nil {
+		return nil, err
+	}
+	explicit, err := d.ListMailboxFolders(mailboxID)
+	if err != nil {
+		return nil, err
+	}
+	seen := make(map[string]bool, len(StandardMailboxFolders)+len(fromMessages)+len(explicit))
+	out := make([]string, 0, len(StandardMailboxFolders)+len(fromMessages)+len(explicit))
+	add := func(f string) {
+		if !seen[f] {
+			seen[f] = true
+			out = append(out, f)
+		}
+	}
+	for _, f := range StandardMailboxFolders {
+		add(f)
+	}
+	for _, f := range fromMessages {
+		add(f)
+	}
+	for _, f := range explicit {
+		add(f)
+	}
+	return out, nil
+}
+
+// unpositionedFolder is the position value a folder row gets when it exists for some
+// other reason (CreateMailboxFolder, rename, becoming a parent) but has never
+// actually been dragged — distinct from 0, which is a legitimate "dragged to the very
+// top" position, so FolderPositions can tell "never ordered" apart from "explicitly
+// ordered first".
+const unpositionedFolder = -1
+
+// FolderPositions returns mailboxID's saved sibling order as {folder name: position}
+// — for folders that have ever been dragged to a specific spot among their siblings
+// (see SetFolderOrder). A folder absent from the map has never been reordered.
+// Positions are only ever compared between actual siblings (see FolderTree); the raw
+// integer means nothing across different parents.
+func (d *DB) FolderPositions(mailboxID int64) (map[string]int, error) {
+	rows, err := d.Query(`SELECT name, position FROM esrv_mailbox_folders WHERE mailbox_id = ? AND position >= 0`, mailboxID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	out := map[string]int{}
+	for rows.Next() {
+		var name string
+		var pos int
+		if err := rows.Scan(&name, &pos); err != nil {
+			return nil, err
+		}
+		out[name] = pos
+	}
+	return out, rows.Err()
+}
+
+// SetFolderOrder persists the drag-and-drop order of one set of siblings in one shot
+// — order is that parent's full children list top to bottom (never the whole tree;
+// positions only mean something relative to siblings, see FolderPositions).
+func (d *DB) SetFolderOrder(mailboxID int64, order []string) error {
+	tx, err := d.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+	for i, name := range order {
+		if _, err := tx.Exec(`INSERT INTO esrv_mailbox_folders (mailbox_id, name, position) VALUES (?, ?, ?)
+			ON CONFLICT(mailbox_id, name) DO UPDATE SET position = excluded.position`, mailboxID, name, i); err != nil {
+			return err
+		}
+	}
+	return tx.Commit()
+}
+
+// folderRow is one esrv_mailbox_folders row, as needed to resolve/rebuild the tree.
+type folderRow struct {
+	id         int64
+	name       string
+	parentID   sql.NullInt64
+	parentRoot string
+	position   int
+}
+
+func (d *DB) allFolderRows(mailboxID int64) ([]folderRow, error) {
+	rows, err := d.Query(`SELECT id, name, parent_id, parent_root, position FROM esrv_mailbox_folders WHERE mailbox_id = ?`, mailboxID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []folderRow
+	for rows.Next() {
+		var r folderRow
+		if err := rows.Scan(&r.id, &r.name, &r.parentID, &r.parentRoot, &r.position); err != nil {
+			return nil, err
+		}
+		out = append(out, r)
+	}
+	return out, rows.Err()
+}
+
+// FolderParentMap returns, for every custom folder that has a row, its immediate
+// parent's current display name (one of the 5 standard names, or another custom
+// folder's current name) — a row with neither parent_id nor parent_root set (legacy
+// data, or a dangling parent_id somehow) defaults to "INBOX", never crashes.
+func (d *DB) FolderParentMap(mailboxID int64) (map[string]string, error) {
+	all, err := d.allFolderRows(mailboxID)
+	if err != nil {
+		return nil, err
+	}
+	byID := make(map[int64]folderRow, len(all))
+	for _, r := range all {
+		byID[r.id] = r
+	}
+	out := make(map[string]string, len(all))
+	for _, r := range all {
+		switch {
+		case r.parentRoot != "":
+			out[r.name] = r.parentRoot
+		case r.parentID.Valid:
+			if p, ok := byID[r.parentID.Int64]; ok {
+				out[r.name] = p.name
+			} else {
+				out[r.name] = "INBOX"
+			}
+		default:
+			out[r.name] = "INBOX"
+		}
+	}
+	return out, nil
+}
+
+// FolderRoot resolves which of the 5 standard folders name ultimately lives under —
+// name itself if it's already standard, otherwise walking up the parent chain. Used
+// to decide "is this folder (still) under INBOX" (renameable, can hold new
+// subfolders) vs "under Trash" (a deleted folder's new home — see
+// webmailDeleteFolder). A cycle or dangling reference (shouldn't happen) falls back
+// to "INBOX" rather than looping forever.
+func (d *DB) FolderRoot(mailboxID int64, name string) (string, error) {
+	if isStandardFolderName(name) {
+		return name, nil
+	}
+	parents, err := d.FolderParentMap(mailboxID)
+	if err != nil {
+		return "", err
+	}
+	seen := map[string]bool{}
+	cur := name
+	for {
+		if isStandardFolderName(cur) {
+			return cur, nil
+		}
+		if seen[cur] {
+			return "INBOX", nil
+		}
+		seen[cur] = true
+		next, ok := parents[cur]
+		if !ok {
+			return "INBOX", nil
+		}
+		cur = next
+	}
+}
+
+// FolderSubtreeNames returns startName plus every descendant folder (any depth) —
+// backs "Empty Trash" (Trash's whole subtree, since deleting a folder re-parents it
+// there) and "Clean up Junk" (Junk never has children, so this is just ["Junk"]) when
+// startName is one of the 5 standard folders, and permanently deleting or restoring
+// one specific custom folder (plus whatever's nested under it) when it isn't.
+func (d *DB) FolderSubtreeNames(mailboxID int64, startName string) ([]string, error) {
+	all, err := d.allFolderRows(mailboxID)
+	if err != nil {
+		return nil, err
+	}
+	inSubtree := map[int64]bool{}
+	for _, r := range all {
+		if r.name == startName {
+			inSubtree[r.id] = true
+			break
+		}
+	}
+	out := []string{startName}
+	// Direct children referencing startName as their standard-root parent — only
+	// matches when startName is itself one of the 5 standard folders.
+	for _, r := range all {
+		if r.parentRoot == startName {
+			out = append(out, r.name)
+			inSubtree[r.id] = true
+		}
+	}
+	// Everything deeper nests via parent_id chains — repeat until a pass finds
+	// nothing new, which correctly handles any depth without a recursive query.
+	for {
+		added := false
+		for _, r := range all {
+			if inSubtree[r.id] {
+				continue
+			}
+			if r.parentID.Valid && inSubtree[r.parentID.Int64] {
+				out = append(out, r.name)
+				inSubtree[r.id] = true
+				added = true
+			}
+		}
+		if !added {
+			break
+		}
+	}
+	return out, nil
+}
+
+// DeleteFolderRows removes esrv_mailbox_folders records for the given names — used
+// after permanently deleting a folder's messages (Empty Trash, Clean up Junk, or
+// permanently deleting one Trash-nested folder), so a permanently-deleted folder
+// doesn't linger as an empty shell in the sidebar the way a merely-emptied one does.
+func (d *DB) DeleteFolderRows(mailboxID int64, names []string) error {
+	if len(names) == 0 {
+		return nil
+	}
+	tx, err := d.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+	for _, name := range names {
+		if _, err := tx.Exec(`DELETE FROM esrv_mailbox_folders WHERE mailbox_id = ? AND name = ?`, mailboxID, name); err != nil {
+			return err
+		}
+	}
+	return tx.Commit()
+}
+
+// FolderNode is one node of the sidebar's actual folder tree — see FolderTree.
+type FolderNode struct {
+	Name       string
+	Children   []*FolderNode
+	Renameable bool // a custom folder still under INBOX (not INBOX itself, not under Trash)
+	CanAddKid  bool // INBOX itself, or a custom folder still under INBOX
+	UnderTrash bool // a custom folder that's been deleted into Trash — can be permanently deleted or restored
+}
+
+// FolderTree builds the mailbox's sidebar tree: the 5 standard folders as fixed-order
+// roots (never reordered relative to each other — see StandardMailboxFolders), each
+// with its custom-folder descendants nested underneath, siblings ordered by any saved
+// drag position (FolderPositions), unpositioned ones keeping insertion order.
+func (d *DB) FolderTree(mailboxID int64) ([]*FolderNode, error) {
+	flat, err := d.AllFoldersForMailbox(mailboxID)
+	if err != nil {
+		return nil, err
+	}
+	parents, err := d.FolderParentMap(mailboxID)
+	if err != nil {
+		return nil, err
+	}
+	positions, err := d.FolderPositions(mailboxID)
+	if err != nil {
+		return nil, err
+	}
+	childrenOf := map[string][]string{}
+	for _, f := range flat {
+		if isStandardFolderName(f) {
+			continue
+		}
+		p := parents[f]
+		childrenOf[p] = append(childrenOf[p], f)
+	}
+	for parent := range childrenOf {
+		kids := childrenOf[parent]
+		sort.SliceStable(kids, func(i, j int) bool {
+			pi, oki := positions[kids[i]]
+			pj, okj := positions[kids[j]]
+			if oki && okj {
+				return pi < pj
+			}
+			return oki && !okj
+		})
+		childrenOf[parent] = kids
+	}
+	var build func(name string) *FolderNode
+	build = func(name string) *FolderNode {
+		root, _ := d.FolderRoot(mailboxID, name)
+		n := &FolderNode{
+			Name:       name,
+			Renameable: !isStandardFolderName(name) && root == "INBOX",
+			CanAddKid:  root == "INBOX",
+			UnderTrash: !isStandardFolderName(name) && root == "Trash",
+		}
+		for _, childName := range childrenOf[name] {
+			n.Children = append(n.Children, build(childName))
+		}
+		return n
+	}
+	roots := make([]*FolderNode, 0, len(StandardMailboxFolders))
+	for _, r := range StandardMailboxFolders {
+		roots = append(roots, build(r))
+	}
+	return roots, nil
+}
+
+// CreateMailboxFolder ensures a folder row exists, purely to hold position/rename
+// metadata — idempotent (INSERT OR IGNORE), so calling it on an already-existing
+// folder is a safe no-op that never clobbers that folder's real parent. Only used
+// when the caller doesn't care about (or already knows) the parent — see
+// CreateMailboxFolderUnder for actually creating a new folder under a chosen parent.
 func (d *DB) CreateMailboxFolder(mailboxID int64, name string) error {
-	_, err := d.Exec(`INSERT OR IGNORE INTO esrv_mailbox_folders (mailbox_id, name) VALUES (?, ?)`, mailboxID, name)
+	_, err := d.Exec(`INSERT OR IGNORE INTO esrv_mailbox_folders (mailbox_id, name, position) VALUES (?, ?, ?)`, mailboxID, name, unpositionedFolder)
 	return err
 }
 
-// DeleteMailboxFolder removes a custom folder's record. Callers are responsible for
-// relocating any messages still in it first (see MoveAllMessagesInFolder) — this
-// alone doesn't touch esrv_mailbox_messages.
-func (d *DB) DeleteMailboxFolder(mailboxID int64, name string) error {
-	_, err := d.Exec(`DELETE FROM esrv_mailbox_folders WHERE mailbox_id = ? AND name = ?`, mailboxID, name)
+// CreateMailboxFolderUnder creates a brand-new custom folder as a child of parent —
+// parent must already be valid (a standard name, or an existing custom folder with
+// its own row) by the time this is called; see webmailAddFolder for the validation
+// this relies on.
+func (d *DB) CreateMailboxFolderUnder(mailboxID int64, name, parent string) error {
+	if isStandardFolderName(parent) {
+		_, err := d.Exec(`INSERT INTO esrv_mailbox_folders (mailbox_id, name, parent_id, parent_root, position) VALUES (?, ?, NULL, ?, ?)`,
+			mailboxID, name, parent, unpositionedFolder)
+		return err
+	}
+	var parentID int64
+	if err := d.QueryRow(`SELECT id FROM esrv_mailbox_folders WHERE mailbox_id = ? AND name = ?`, mailboxID, parent).Scan(&parentID); err != nil {
+		return err
+	}
+	_, err := d.Exec(`INSERT INTO esrv_mailbox_folders (mailbox_id, name, parent_id, parent_root, position) VALUES (?, ?, ?, '', ?)`,
+		mailboxID, name, parentID, unpositionedFolder)
+	return err
+}
+
+// MoveFolderToTrash re-parents a folder (and, since its descendants reference it by
+// id rather than a materialized path, its whole subtree along with it) under Trash —
+// this IS "delete a folder": see webmailDeleteFolder for why messages are never
+// separately relocated. Captures the folder's current parent into
+// restore_parent_id/restore_parent_root first, so RestoreFolder can put it back where
+// it came from later.
+func (d *DB) MoveFolderToTrash(mailboxID int64, name string) error {
+	tx, err := d.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+
+	var id int64
+	var parentID sql.NullInt64
+	var parentRoot string
+	err = tx.QueryRow(`SELECT id, parent_id, parent_root FROM esrv_mailbox_folders WHERE mailbox_id = ? AND name = ?`, mailboxID, name).
+		Scan(&id, &parentID, &parentRoot)
+	switch {
+	case errors.Is(err, sql.ErrNoRows):
+		// No row yet (a message-derived-only folder, never explicitly parented) — its
+		// restore target defaults to INBOX, the same default FolderParentMap already
+		// uses for a row-less folder.
+		if _, err := tx.Exec(`INSERT INTO esrv_mailbox_folders (mailbox_id, name, parent_id, parent_root, restore_parent_id, restore_parent_root, position) VALUES (?, ?, NULL, 'Trash', NULL, 'INBOX', ?)`,
+			mailboxID, name, unpositionedFolder); err != nil {
+			return err
+		}
+	case err != nil:
+		return err
+	default:
+		restoreRoot := parentRoot
+		if !parentID.Valid && parentRoot == "" {
+			restoreRoot = "INBOX"
+		}
+		if _, err := tx.Exec(`UPDATE esrv_mailbox_folders SET restore_parent_id = ?, restore_parent_root = ?, parent_id = NULL, parent_root = 'Trash' WHERE id = ?`,
+			parentID, restoreRoot, id); err != nil {
+			return err
+		}
+	}
+	return tx.Commit()
+}
+
+// RestoreFolder re-parents a folder back to where it was the moment it was deleted
+// (see MoveFolderToTrash's restore_parent_id/restore_parent_root capture), falling
+// back to INBOX if that's no longer meaningful — its former parent has itself since
+// been deleted into Trash too, so restoring underneath it would leave this folder
+// looking un-restored (still inside Trash's subtree).
+func (d *DB) RestoreFolder(mailboxID int64, name string) error {
+	var restoreParentID sql.NullInt64
+	var restoreParentRoot string
+	if err := d.QueryRow(`SELECT restore_parent_id, restore_parent_root FROM esrv_mailbox_folders WHERE mailbox_id = ? AND name = ?`, mailboxID, name).
+		Scan(&restoreParentID, &restoreParentRoot); err != nil {
+		return err
+	}
+
+	parentID := restoreParentID
+	parentRoot := restoreParentRoot
+	if parentID.Valid {
+		valid := false
+		var parentName string
+		if err := d.QueryRow(`SELECT name FROM esrv_mailbox_folders WHERE id = ?`, parentID.Int64).Scan(&parentName); err == nil {
+			if root, err := d.FolderRoot(mailboxID, parentName); err == nil && root != "Trash" {
+				valid = true
+			}
+		}
+		if valid {
+			parentRoot = ""
+		} else {
+			parentID = sql.NullInt64{}
+			parentRoot = "INBOX"
+		}
+	} else if parentRoot == "" {
+		parentRoot = "INBOX"
+	}
+
+	_, err := d.Exec(`UPDATE esrv_mailbox_folders SET parent_id = ?, parent_root = ?, restore_parent_id = NULL, restore_parent_root = '' WHERE mailbox_id = ? AND name = ?`,
+		parentID, parentRoot, mailboxID, name)
 	return err
 }
 
@@ -36,10 +468,20 @@ func (d *DB) ListMailboxFolders(mailboxID int64) ([]string, error) {
 	return out, rows.Err()
 }
 
-// MoveAllMessagesInFolder reassigns every message in one folder to another — used
-// when deleting a custom folder, so its messages land in INBOX instead of becoming
-// orphaned in a folder nothing lists anymore.
-func (d *DB) MoveAllMessagesInFolder(mailboxID int64, from, to string) error {
-	_, err := d.Exec(`UPDATE esrv_mailbox_messages SET folder = ? WHERE mailbox_id = ? AND folder = ?`, to, mailboxID, from)
+// RenameMailboxFolder changes a folder's display name only — a single-row UPDATE is
+// enough (no cascade needed): children reference their parent by row id, not by name,
+// so they stay correctly nested with zero further writes.
+func (d *DB) RenameMailboxFolder(mailboxID int64, oldName, newName string) error {
+	tx, err := d.Begin()
+	if err != nil {
 		return err
+	}
+	defer tx.Rollback()
+	if _, err := tx.Exec(`UPDATE esrv_mailbox_folders SET name = ? WHERE mailbox_id = ? AND name = ?`, newName, mailboxID, oldName); err != nil {
+		return err
+	}
+	if _, err := tx.Exec(`UPDATE esrv_mailbox_messages SET folder = ? WHERE mailbox_id = ? AND folder = ?`, newName, mailboxID, oldName); err != nil {
+		return err
+	}
+	return tx.Commit()
 }

internal/db/crud_mailbox_folders_test.go

@@ -0,0 +1,297 @@
+package db
+
+import "testing"
+
+// TestCreateMailboxFolderDoesNotDisturbOrder is a regression test for a real bug
+// caught via live testing: CreateMailboxFolder's INSERT OR IGNORE used to leave a
+// fresh row's position at the column's SQL default (0), which is indistinguishable
+// from "explicitly dragged to the very top" — so creating a brand-new custom folder
+// made it jump above INBOX in the sidebar the instant it was created, before the user
+// ever touched drag-and-drop. Fixed by writing an explicit sentinel (unpositionedFolder,
+// -1) for a row that exists but was never dragged.
+func TestCreateMailboxFolderDoesNotDisturbOrder(t *testing.T) {
+	d := openTestDB(t)
+	const mailboxID = int64(1)
+
+	if err := d.CreateMailboxFolder(mailboxID, "Receipts"); err != nil {
+		t.Fatal(err)
+	}
+	folders, err := d.AllFoldersForMailbox(mailboxID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(folders) == 0 || folders[0] != "INBOX" {
+		t.Fatalf("expected INBOX first, got %v", folders)
+	}
+	if folders[len(folders)-1] != "Receipts" {
+		t.Fatalf("expected Receipts last (never dragged), got %v", folders)
+	}
+}
+
+// treeNames flattens a []*FolderNode into a depth-first name list for easy assertion.
+func treeNames(nodes []*FolderNode) []string {
+	var out []string
+	var walk func(n *FolderNode)
+	walk = func(n *FolderNode) {
+		out = append(out, n.Name)
+		for _, c := range n.Children {
+			walk(c)
+		}
+	}
+	for _, n := range nodes {
+		walk(n)
+	}
+	return out
+}
+
+// TestAllFoldersForMailboxRootOrderIsFixed confirms the 5 standard folders are always
+// returned in their fixed StandardMailboxFolders order — root folders are static and
+// were deliberately made non-reorderable, so even a stray saved position for one
+// (however it got there) must never change their relative order.
+func TestAllFoldersForMailboxRootOrderIsFixed(t *testing.T) {
+	d := openTestDB(t)
+	const mailboxID = int64(1)
+
+	if err := d.SetFolderOrder(mailboxID, []string{"Trash", "Junk", "INBOX", "Drafts", "Sent"}); err != nil {
+		t.Fatal(err)
+	}
+	folders, err := d.AllFoldersForMailbox(mailboxID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := []string{"INBOX", "Junk", "Sent", "Drafts", "Trash"}
+	if len(folders) != len(want) {
+		t.Fatalf("folders = %v, want %v", folders, want)
+	}
+	for i, name := range want {
+		if folders[i] != name {
+			t.Fatalf("folders = %v, want %v", folders, want)
+		}
+	}
+}
+
+// TestFolderTreeNestsUnderParentAndOrdersSiblings confirms CreateMailboxFolderUnder
+// actually nests a folder under its chosen parent in FolderTree, and that a saved
+// sibling order (SetFolderOrder, scoped to just that parent's children) is respected
+// — a folder created afterwards (never dragged) appends after the ordered siblings.
+func TestFolderTreeNestsUnderParentAndOrdersSiblings(t *testing.T) {
+	d := openTestDB(t)
+	const mailboxID = int64(1)
+
+	if err := d.CreateMailboxFolderUnder(mailboxID, "Projects", "INBOX"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.CreateMailboxFolderUnder(mailboxID, "ClientA", "Projects"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.CreateMailboxFolderUnder(mailboxID, "ClientB", "Projects"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.SetFolderOrder(mailboxID, []string{"ClientB", "ClientA"}); err != nil {
+		t.Fatal(err)
+	}
+
+	tree, err := d.FolderTree(mailboxID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got := treeNames(tree)
+	want := []string{"INBOX", "Projects", "ClientB", "ClientA", "Junk", "Sent", "Drafts", "Trash"}
+	if len(got) != len(want) {
+		t.Fatalf("tree = %v, want %v", got, want)
+	}
+	for i, name := range want {
+		if got[i] != name {
+			t.Fatalf("tree = %v, want %v", got, want)
+		}
+	}
+
+	if err := d.CreateMailboxFolderUnder(mailboxID, "ClientC", "Projects"); err != nil {
+		t.Fatal(err)
+	}
+	tree, err = d.FolderTree(mailboxID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got = treeNames(tree)
+	if got[len(got)-5] != "ClientC" { // last of Projects' 3 children, before Junk/Sent/Drafts/Trash
+		t.Fatalf("expected ClientC to append after the ordered siblings, got %v", got)
+	}
+}
+
+// TestRenameMailboxFolderKeepsChildrenNested confirms renaming a folder that has
+// children leaves them correctly nested (they reference their parent by row id, not
+// by name, so a plain single-row UPDATE never orphans them).
+func TestRenameMailboxFolderKeepsChildrenNested(t *testing.T) {
+	d := openTestDB(t)
+	const mailboxID = int64(1)
+
+	if err := d.CreateMailboxFolderUnder(mailboxID, "Projects", "INBOX"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.CreateMailboxFolderUnder(mailboxID, "ClientA", "Projects"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.RenameMailboxFolder(mailboxID, "Projects", "Work"); err != nil {
+		t.Fatal(err)
+	}
+
+	root, err := d.FolderRoot(mailboxID, "ClientA")
+	if err != nil || root != "INBOX" {
+		t.Fatalf("expected ClientA to still resolve under INBOX after its parent was renamed, root=%q err=%v", root, err)
+	}
+	tree, err := d.FolderTree(mailboxID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got := treeNames(tree)
+	want := []string{"INBOX", "Work", "ClientA", "Junk", "Sent", "Drafts", "Trash"}
+	if len(got) != len(want) {
+		t.Fatalf("tree = %v, want %v", got, want)
+	}
+	for i, name := range want {
+		if got[i] != name {
+			t.Fatalf("tree = %v, want %v", got, want)
+		}
+	}
+}
+
+// TestMoveFolderToTrashKeepsSubtreeIntact confirms deleting a folder that has its own
+// children re-parents the whole subtree under Trash in one move — the children,
+// referencing their parent by id, come along automatically with zero further writes.
+func TestMoveFolderToTrashKeepsSubtreeIntact(t *testing.T) {
+	d := openTestDB(t)
+	const mailboxID = int64(1)
+
+	if err := d.CreateMailboxFolderUnder(mailboxID, "Projects", "INBOX"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.CreateMailboxFolderUnder(mailboxID, "ClientA", "Projects"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.MoveFolderToTrash(mailboxID, "Projects"); err != nil {
+		t.Fatal(err)
+	}
+
+	for _, name := range []string{"Projects", "ClientA"} {
+		root, err := d.FolderRoot(mailboxID, name)
+		if err != nil || root != "Trash" {
+			t.Fatalf("expected %s to resolve under Trash, got root=%q (err=%v)", name, root, err)
+		}
+	}
+	names, err := d.FolderSubtreeNames(mailboxID, "Trash")
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := map[string]bool{"Trash": true, "Projects": true, "ClientA": true}
+	if len(names) != len(want) {
+		t.Fatalf("FolderSubtreeNames(Trash) = %v, want exactly %v", names, want)
+	}
+	for _, n := range names {
+		if !want[n] {
+			t.Fatalf("FolderSubtreeNames(Trash) = %v, want exactly %v", names, want)
+		}
+	}
+}
+
+// TestRestoreFolderReturnsToOriginalParent confirms deleting a nested folder and then
+// restoring it puts it back exactly where it was (not just dumped at INBOX's top
+// level) — its sibling, untouched throughout, proves the parent (Projects) itself
+// never moved.
+func TestRestoreFolderReturnsToOriginalParent(t *testing.T) {
+	d := openTestDB(t)
+	const mailboxID = int64(1)
+
+	if err := d.CreateMailboxFolderUnder(mailboxID, "Projects", "INBOX"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.CreateMailboxFolderUnder(mailboxID, "ClientA", "Projects"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.MoveFolderToTrash(mailboxID, "ClientA"); err != nil {
+		t.Fatal(err)
+	}
+	if root, err := d.FolderRoot(mailboxID, "ClientA"); err != nil || root != "Trash" {
+		t.Fatalf("expected ClientA under Trash after delete, root=%q err=%v", root, err)
+	}
+
+	if err := d.RestoreFolder(mailboxID, "ClientA"); err != nil {
+		t.Fatal(err)
+	}
+	tree, err := d.FolderTree(mailboxID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got := treeNames(tree)
+	want := []string{"INBOX", "Projects", "ClientA", "Junk", "Sent", "Drafts", "Trash"}
+	if len(got) != len(want) {
+		t.Fatalf("tree after restore = %v, want %v", got, want)
+	}
+	for i, name := range want {
+		if got[i] != name {
+			t.Fatalf("tree after restore = %v, want %v", got, want)
+		}
+	}
+}
+
+// TestRestoreFolderFallsBackToInboxWhenOriginalParentStillTrashed confirms restoring
+// a folder whose former parent is itself still in Trash doesn't leave it looking
+// un-restored (nested inside another trashed folder) — it falls back to INBOX
+// instead.
+func TestRestoreFolderFallsBackToInboxWhenOriginalParentStillTrashed(t *testing.T) {
+	d := openTestDB(t)
+	const mailboxID = int64(1)
+
+	if err := d.CreateMailboxFolderUnder(mailboxID, "Projects", "INBOX"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.CreateMailboxFolderUnder(mailboxID, "ClientA", "Projects"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.MoveFolderToTrash(mailboxID, "ClientA"); err != nil {
+		t.Fatal(err)
+	}
+	// Now trash Projects too — ClientA's restore target (Projects) is itself trashed.
+	if err := d.MoveFolderToTrash(mailboxID, "Projects"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.RestoreFolder(mailboxID, "ClientA"); err != nil {
+		t.Fatal(err)
+	}
+	root, err := d.FolderRoot(mailboxID, "ClientA")
+	if err != nil || root != "INBOX" {
+		t.Fatalf("expected ClientA to fall back under INBOX, got root=%q (err=%v)", root, err)
+	}
+}
+
+// TestDeleteFolderRowsRemovesRecords confirms DeleteFolderRows actually removes the
+// esrv_mailbox_folders rows (not just messages) — used by permanent deletes so a
+// permanently-removed folder doesn't linger as an empty shell in FolderTree.
+func TestDeleteFolderRowsRemovesRecords(t *testing.T) {
+	d := openTestDB(t)
+	const mailboxID = int64(1)
+
+	if err := d.CreateMailboxFolderUnder(mailboxID, "Projects", "INBOX"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.CreateMailboxFolderUnder(mailboxID, "ClientA", "Projects"); err != nil {
+		t.Fatal(err)
+	}
+	if err := d.DeleteFolderRows(mailboxID, []string{"Projects", "ClientA"}); err != nil {
+		t.Fatal(err)
+	}
+	tree, err := d.FolderTree(mailboxID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got := treeNames(tree)
+	want := []string{"INBOX", "Junk", "Sent", "Drafts", "Trash"}
+	if len(got) != len(want) {
+		t.Fatalf("tree after DeleteFolderRows = %v, want %v (Projects/ClientA gone)", got, want)
+	}
+	for i, name := range want {
+		if got[i] != name {
+			t.Fatalf("tree after DeleteFolderRows = %v, want %v", got, want)
+		}
+	}
+}

internal/db/crud_mailbox_messages.go

@@ -59,6 +59,33 @@ func (d *DB) MoveMessage(mailboxID, uid int64, newFolder string) error {
 	return err
 }
 
+// MoveMessageToTrash moves a message to Trash, first capturing its current folder
+// into restore_folder so RestoreMessage can put it back later (mirrors
+// db.MoveFolderToTrash's identical capture for folders).
+func (d *DB) MoveMessageToTrash(mailboxID, uid int64) error {
+	var folder string
+	if err := d.QueryRow(`SELECT folder FROM esrv_mailbox_messages WHERE id = ? AND mailbox_id = ?`, uid, mailboxID).Scan(&folder); err != nil {
+		return err
+	}
+	_, err := d.Exec(`UPDATE esrv_mailbox_messages SET restore_folder = ?, folder = 'Trash' WHERE id = ? AND mailbox_id = ?`, folder, uid, mailboxID)
+	return err
+}
+
+// RestoreMessage moves a message back to the folder it was in immediately before
+// being moved to Trash (see MoveMessageToTrash), or INBOX if that's unknown (e.g. a
+// message trashed before this feature existed, or moved to Trash some other way).
+func (d *DB) RestoreMessage(mailboxID, uid int64) error {
+	var restoreFolder string
+	if err := d.QueryRow(`SELECT restore_folder FROM esrv_mailbox_messages WHERE id = ? AND mailbox_id = ?`, uid, mailboxID).Scan(&restoreFolder); err != nil {
+		return err
+	}
+	if restoreFolder == "" {
+		restoreFolder = "INBOX"
+	}
+	_, err := d.Exec(`UPDATE esrv_mailbox_messages SET folder = ?, restore_folder = '' WHERE id = ? AND mailbox_id = ?`, restoreFolder, uid, mailboxID)
+	return err
+}
+
 // ListMessageUIDsForMailbox returns every stored message's UID for mailboxID — used by
 // mailbox removal to delete each one's on-disk ciphertext via mailstore before the
 // mailbox row itself is removed.
@@ -155,12 +182,15 @@ func sortColumnAndDir(sortBy, sortDir string) string {
 	return col + " " + dir + ", id " + dir
 }
 
-func (d *DB) ListMessagesInFolderPage(mailboxID int64, folder string, unreadOnly bool, sortBy, sortDir string, offset, limit int) ([]MailboxMessage, error) {
+func (d *DB) ListMessagesInFolderPage(mailboxID int64, folder string, unreadOnly, starredOnly bool, sortBy, sortDir string, offset, limit int) ([]MailboxMessage, error) {
 	query := `SELECT ` + mailboxMessageColumns + ` FROM esrv_mailbox_messages WHERE mailbox_id = ? AND folder = ?`
 	args := []any{mailboxID, folder}
 	if unreadOnly {
 		query += ` AND flags NOT LIKE '%\Seen%' ESCAPE '\'`
 	}
+	if starredOnly {
+		query += ` AND flags LIKE '%\Flagged%' ESCAPE '\'`
+	}
 	query += ` ORDER BY ` + sortColumnAndDir(sortBy, sortDir) + ` LIMIT ? OFFSET ?`
 	args = append(args, limit, offset)
 	rows, err := d.Query(query, args...)
@@ -171,17 +201,59 @@ func (d *DB) ListMessagesInFolderPage(mailboxID int64, folder string, unreadOnly
 }
 
 // CountMessagesInFolder backs ListMessagesInFolderPage's pagination controls.
-func (d *DB) CountMessagesInFolder(mailboxID int64, folder string, unreadOnly bool) (int, error) {
+func (d *DB) CountMessagesInFolder(mailboxID int64, folder string, unreadOnly, starredOnly bool) (int, error) {
 	query := `SELECT COUNT(*) FROM esrv_mailbox_messages WHERE mailbox_id = ? AND folder = ?`
 	args := []any{mailboxID, folder}
 	if unreadOnly {
 		query += ` AND flags NOT LIKE '%\Seen%' ESCAPE '\'`
 	}
+	if starredOnly {
+		query += ` AND flags LIKE '%\Flagged%' ESCAPE '\'`
+	}
 	var n int
 	err := d.QueryRow(query, args...).Scan(&n)
 	return n, err
 }
 
+// MarkAllReadInFolder adds \Seen to every currently-unread message in one folder —
+// the folder-context-menu "Mark all as read" action's bulk equivalent of opening each
+// message individually. Messages that already have other flags (e.g. \Flagged) keep
+// them; only \Seen is added.
+func (d *DB) MarkAllReadInFolder(mailboxID int64, folder string) error {
+	_, err := d.Exec(`UPDATE esrv_mailbox_messages SET flags = TRIM(flags || ' \Seen')
+		WHERE mailbox_id = ? AND folder = ? AND flags NOT LIKE '%\Seen%' ESCAPE '\'`, mailboxID, folder)
+	return err
+}
+
+// ToggleMessageStarred flips \Flagged (IMAP's standard "starred/important" flag) on
+// one message — reusing the existing flags column instead of a new schema column
+// keeps this consistent with a desktop IMAP client's own star/flag button acting on
+// the same message.
+func (d *DB) ToggleMessageStarred(mailboxID, uid int64) error {
+	msg, err := d.GetMessageByUID(mailboxID, uid)
+	if err != nil || msg == nil {
+		return err
+	}
+	var newFlags string
+	if isStarred(msg.Flags) {
+		newFlags = strings.TrimSpace(strings.ReplaceAll(msg.Flags, `\Flagged`, ""))
+	} else {
+		newFlags = strings.TrimSpace(msg.Flags + ` \Flagged`)
+	}
+	return d.SetMessageFlags(mailboxID, uid, newFlags)
+}
+
+// isStarred reports whether flags (the same space-separated IMAP flags string
+// isUnread checks in internal/webui) includes \Flagged.
+func isStarred(flags string) bool {
+	for _, f := range strings.Fields(flags) {
+		if f == `\Flagged` {
+			return true
+		}
+	}
+	return false
+}
+
 // escapeLike backslash-escapes a user-supplied LIKE pattern's own special characters
 // (%, _, and the escape character itself) so a search for e.g. "50% off" or a
 // filename with an underscore doesn't get interpreted as a wildcard.

internal/db/crud_mailbox_signatures.go

@@ -0,0 +1,107 @@
+package db
+
+import (
+	"database/sql"
+	"errors"
+)
+
+const signatureColumns = `id, mailbox_id, name, content_html, is_default_new, is_default_reply, created_at`
+
+func scanSignature(scan func(dest ...any) error) (MailboxSignature, error) {
+	var s MailboxSignature
+	var createdAt string
+	err := scan(&s.ID, &s.MailboxID, &s.Name, &s.ContentHTML, &s.IsDefaultNew, &s.IsDefaultReply, &createdAt)
+	if err != nil {
+		return s, err
+	}
+	s.CreatedAt, _ = parseTime(createdAt)
+	return s, nil
+}
+
+// ListSignatures returns a mailbox's saved signatures, most recently created first.
+func (d *DB) ListSignatures(mailboxID int64) ([]MailboxSignature, error) {
+	rows, err := d.Query(`SELECT `+signatureColumns+` FROM esrv_mailbox_signatures WHERE mailbox_id = ? ORDER BY id DESC`, mailboxID)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []MailboxSignature
+	for rows.Next() {
+		s, err := scanSignature(rows.Scan)
+		if err != nil {
+			return nil, err
+		}
+		out = append(out, s)
+	}
+	return out, rows.Err()
+}
+
+// GetSignatureByID scopes the lookup to mailboxID so one mailbox can never read or
+// (via UpdateSignature/DeleteSignature, which reuse this same WHERE clause) modify
+// another's signature by guessing an id.
+func (d *DB) GetSignatureByID(mailboxID, id int64) (*MailboxSignature, error) {
+	row := d.QueryRow(`SELECT `+signatureColumns+` FROM esrv_mailbox_signatures WHERE id = ? AND mailbox_id = ?`, id, mailboxID)
+	s, err := scanSignature(row.Scan)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			return nil, nil
+		}
+		return nil, err
+	}
+	return &s, nil
+}
+
+// GetDefaultSignature returns the mailbox's default-for-new (forReply=false) or
+// default-for-reply/forward (forReply=true) signature, or nil if none is set.
+func (d *DB) GetDefaultSignature(mailboxID int64, forReply bool) (*MailboxSignature, error) {
+	col := "is_default_new"
+	if forReply {
+		col = "is_default_reply"
+	}
+	row := d.QueryRow(`SELECT `+signatureColumns+` FROM esrv_mailbox_signatures WHERE mailbox_id = ? AND `+col+` = 1 LIMIT 1`, mailboxID)
+	s, err := scanSignature(row.Scan)
+	if err != nil {
+		if errors.Is(err, sql.ErrNoRows) {
+			return nil, nil
+		}
+		return nil, err
+	}
+	return &s, nil
+}
+
+func (d *DB) CreateSignature(mailboxID int64, name, contentHTML string) (int64, error) {
+	res, err := d.Exec(`INSERT INTO esrv_mailbox_signatures (mailbox_id, name, content_html) VALUES (?, ?, ?)`, mailboxID, name, contentHTML)
+	if err != nil {
+		return 0, err
+	}
+	return res.LastInsertId()
+}
+
+func (d *DB) UpdateSignature(mailboxID, id int64, name, contentHTML string) error {
+	_, err := d.Exec(`UPDATE esrv_mailbox_signatures SET name = ?, content_html = ? WHERE id = ? AND mailbox_id = ?`, name, contentHTML, id, mailboxID)
+	return err
+}
+
+func (d *DB) DeleteSignature(mailboxID, id int64) error {
+	_, err := d.Exec(`DELETE FROM esrv_mailbox_signatures WHERE id = ? AND mailbox_id = ?`, id, mailboxID)
+	return err
+}
+
+// SetDefaultSignature makes id the mailbox's default-for-new (forReply=false) or
+// default-for-reply/forward (forReply=true) signature, clearing the flag from every
+// other row first so at most one ever holds it — id=0 just clears the flag from
+// everything, i.e. "no default".
+func (d *DB) SetDefaultSignature(mailboxID, id int64, forReply bool) error {
+	col := "is_default_new"
+	if forReply {
+		col = "is_default_reply"
+	}
+	if _, err := d.Exec(`UPDATE esrv_mailbox_signatures SET `+col+` = 0 WHERE mailbox_id = ?`, mailboxID); err != nil {
+		return err
+	}
+	if id == 0 {
+		return nil
+	}
+	_, err := d.Exec(`UPDATE esrv_mailbox_signatures SET `+col+` = 1 WHERE id = ? AND mailbox_id = ?`, id, mailboxID)
+	return err
+}

internal/db/mailbox_models.go

@@ -152,6 +152,19 @@ type MailboxMessage struct {
 	CreatedAt       time.Time
 }
 
+// MailboxSignature is one of a mailbox's saved email signatures — HTML content, shown
+// as an option in compose and optionally auto-inserted for a new message or a
+// reply/forward (IsDefaultNew/IsDefaultReply).
+type MailboxSignature struct {
+	ID             int64
+	MailboxID      int64
+	Name           string
+	ContentHTML    string
+	IsDefaultNew   bool
+	IsDefaultReply bool
+	CreatedAt      time.Time
+}
+
 // MailboxSMIMEIdentity is one of a mailbox's own S/MIME certificate + private key
 // pairs — a mailbox may hold several. Both halves are stored plain: S/MIME is
 // sign-only in this codebase, so the key never protects anything beyond what the

internal/db/message_restore_test.go

@@ -0,0 +1,53 @@
+package db
+
+import (
+	"testing"
+	"time"
+)
+
+// TestMoveMessageToTrashAndRestore confirms a message trashed via MoveMessageToTrash
+// remembers its prior folder and RestoreMessage puts it back there.
+func TestMoveMessageToTrashAndRestore(t *testing.T) {
+	d := openTestDB(t)
+	const mailboxID = int64(1)
+
+	uid, err := d.InsertMessage(mailboxID, "Newsletters", "", "", time.Now(), 10, "/dev/null", []byte("nonce"), "a@example.com", "b@example.com", "subj", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := d.MoveMessageToTrash(mailboxID, uid); err != nil {
+		t.Fatal(err)
+	}
+	msg, err := d.GetMessageByUID(mailboxID, uid)
+	if err != nil || msg.Folder != "Trash" {
+		t.Fatalf("expected message in Trash, got folder=%q (err=%v)", msg.Folder, err)
+	}
+
+	if err := d.RestoreMessage(mailboxID, uid); err != nil {
+		t.Fatal(err)
+	}
+	msg, err = d.GetMessageByUID(mailboxID, uid)
+	if err != nil || msg.Folder != "Newsletters" {
+		t.Fatalf("expected message restored to Newsletters, got folder=%q (err=%v)", msg.Folder, err)
+	}
+}
+
+// TestRestoreMessageFallsBackToInboxWhenUnknown confirms a message with no recorded
+// restore_folder (e.g. trashed before this feature existed) restores to INBOX rather
+// than erroring or restoring to an empty folder name.
+func TestRestoreMessageFallsBackToInboxWhenUnknown(t *testing.T) {
+	d := openTestDB(t)
+	const mailboxID = int64(1)
+
+	uid, err := d.InsertMessage(mailboxID, "Trash", "", "", time.Now(), 10, "/dev/null", []byte("nonce"), "a@example.com", "b@example.com", "subj", "")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := d.RestoreMessage(mailboxID, uid); err != nil {
+		t.Fatal(err)
+	}
+	msg, err := d.GetMessageByUID(mailboxID, uid)
+	if err != nil || msg.Folder != "INBOX" {
+		t.Fatalf("expected fallback to INBOX, got folder=%q (err=%v)", msg.Folder, err)
+	}
+}

internal/db/schema.go

@@ -316,6 +316,11 @@ CREATE TABLE IF NOT EXISTS esrv_mailbox_messages (
 	-- other cached_* columns) so the folder list can show a preview snippet without
 	-- decrypting the full message just to render the list.
 	cached_preview TEXT NOT NULL DEFAULT '',
+	-- Snapshot of folder taken the moment a message is moved to Trash (see
+	-- db.MoveMessageToTrash), so "Restore" (db.RestoreMessage) can put it back where
+	-- it came from instead of just dumping it in INBOX. Empty outside of that window
+	-- (cleared again once restored).
+	restore_folder TEXT NOT NULL DEFAULT '',
 	storage_path TEXT NOT NULL,
 	nonce BLOB NOT NULL,
 	created_at DATETIME DEFAULT CURRENT_TIMESTAMP
@@ -328,13 +333,47 @@ CREATE INDEX IF NOT EXISTS idx_mailbox_messages_folder ON esrv_mailbox_messages(
 
 -- Explicit record of a mailbox's custom folders, so a freshly created (still empty)
 -- one shows up in the folder list — esrv_mailbox_messages.folder alone can only prove
--- a folder exists once it holds at least one message. Standard folders (INBOX, Spam,
--- Sent, Drafts, Trash) are never stored here; they're always shown by the webui
--- regardless of this table.
+-- a folder exists once it holds at least one message. Standard folders (INBOX, Junk,
+-- Sent, Drafts, Trash) don't need a row to be listed — they're always shown by the
+-- webui regardless — but DO get one the first time they're renamed, dragged to a new
+-- position, or made a parent, purely to hold that metadata (see CreateMailboxFolder,
+-- SetFolderOrder).
+--
+-- Custom folders form a real tree, always rooted at one of the 5 standard folders
+-- (webui only ever offers "New folder" under INBOX, and "delete a folder" re-parents
+-- it under Trash — see webmailDeleteFolder). Exactly one of parent_id/parent_root is
+-- ever set per row: parent_id (an id, not a name) when the parent is another custom
+-- folder — immune to that parent later being renamed, unlike a name-based reference —
+-- parent_root (one of the 5 fixed, never-renamed standard names) when the parent is a
+-- standard folder that may not have its own row. A row with BOTH unset (parent_id
+-- NULL, parent_root '') is legacy data predating this column and is treated as
+-- "under INBOX" (see db.FolderParentMap) — every custom folder created before this
+-- feature was flat/top-level anyway, so that default is exactly correct, no backfill
+-- migration needed.
+--
+-- esrv_mailbox_messages.folder itself is untouched by any of this — messages are
+-- still tagged with a flat folder name exactly as before; the parent/child
+-- relationship here is purely an organizational layer for the sidebar.
 CREATE TABLE IF NOT EXISTS esrv_mailbox_folders (
 	id INTEGER PRIMARY KEY AUTOINCREMENT,
 	mailbox_id INTEGER NOT NULL REFERENCES esrv_mailboxes(id),
 	name TEXT NOT NULL,
+	parent_id INTEGER REFERENCES esrv_mailbox_folders(id),
+	parent_root TEXT NOT NULL DEFAULT '',
+	-- Sidebar sort position among this folder's siblings (lower first), set only once
+	-- the user drags to reorder. The app always writes an explicit value: -1
+	-- (db.unpositionedFolder) for a row that exists for some other reason (rename, a
+	-- folder just created, becoming a parent) but was never dragged, so it doesn't
+	-- look like a real "dragged to the very top" (0) — FolderPositions filters on
+	-- position >= 0 for exactly this reason. Column default of 0 is inert (every write
+	-- path is explicit); kept only as a harmless fallback.
+	position INTEGER NOT NULL DEFAULT 0,
+	-- Snapshot of parent_id/parent_root taken the moment a folder is deleted (moved
+	-- under Trash — see db.MoveFolderToTrash), so "Restore" (db.RestoreFolder) can put
+	-- it back where it came from instead of just dumping it at INBOX's top level.
+	-- Empty/NULL outside of that window (cleared again once restored).
+	restore_parent_id INTEGER REFERENCES esrv_mailbox_folders(id),
+	restore_parent_root TEXT NOT NULL DEFAULT '',
 	created_at DATETIME DEFAULT CURRENT_TIMESTAMP,
 	UNIQUE(mailbox_id, name)
 );
@@ -391,6 +430,25 @@ CREATE TABLE IF NOT EXISTS esrv_mailbox_pgp_identities (
 	created_at DATETIME DEFAULT CURRENT_TIMESTAMP
 );
 
+-- A mailbox's saved email signatures — HTML content (compose is HTML/Quill-based
+-- already; a plain-text signature is just HTML with no formatting, so one content
+-- column covers both instead of storing two parallel copies). A mailbox may hold
+-- several, e.g. one formal and one casual; is_default_new/is_default_reply pick which
+-- one (if any) compose pre-fills for a brand-new message vs a reply/forward — at most
+-- one row per mailbox should have each flag set, enforced in the db package (Go), not
+-- a SQL constraint, since "make this one the default" is naturally an
+-- update-this-then-clear-the-others operation either way.
+CREATE TABLE IF NOT EXISTS esrv_mailbox_signatures (
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	mailbox_id INTEGER NOT NULL REFERENCES esrv_mailboxes(id),
+	name TEXT NOT NULL,
+	content_html TEXT NOT NULL DEFAULT '',
+	is_default_new INTEGER NOT NULL DEFAULT 0,
+	is_default_reply INTEGER NOT NULL DEFAULT 0,
+	created_at DATETIME DEFAULT CURRENT_TIMESTAMP
+);
+CREATE INDEX IF NOT EXISTS idx_mailbox_signatures_mailbox ON esrv_mailbox_signatures(mailbox_id);
+
 -- Other people's PGP public keys a mailbox owner has collected, added by hand —
 -- mirrors esrv_mailbox_smime_contacts. Used to offer "Encrypt (PGP)" for a
 -- recipient in compose.
@@ -441,6 +499,12 @@ func migrateAddedColumns(db *sql.DB) {
 		`ALTER TABLE esrv_mailbox_smime_identities ADD COLUMN key_pem TEXT NOT NULL DEFAULT ''`,
 		`ALTER TABLE esrv_mailboxes ADD COLUMN group_messages INTEGER NOT NULL DEFAULT 0`,
 		`ALTER TABLE esrv_mailbox_messages ADD COLUMN cached_preview TEXT NOT NULL DEFAULT ''`,
+		`ALTER TABLE esrv_mailbox_folders ADD COLUMN position INTEGER NOT NULL DEFAULT 0`,
+		`ALTER TABLE esrv_mailbox_folders ADD COLUMN parent_id INTEGER REFERENCES esrv_mailbox_folders(id)`,
+		`ALTER TABLE esrv_mailbox_folders ADD COLUMN parent_root TEXT NOT NULL DEFAULT ''`,
+		`ALTER TABLE esrv_mailbox_folders ADD COLUMN restore_parent_id INTEGER REFERENCES esrv_mailbox_folders(id)`,
+		`ALTER TABLE esrv_mailbox_folders ADD COLUMN restore_parent_root TEXT NOT NULL DEFAULT ''`,
+		`ALTER TABLE esrv_mailbox_messages ADD COLUMN restore_folder TEXT NOT NULL DEFAULT ''`,
 	}
 	// The three old columns above were NOT NULL with no default, so simply adding
 	// key_pem left them behind still blocking every new insert (which only ever sets
@@ -458,6 +522,23 @@ func migrateAddedColumns(db *sql.DB) {
 	// defaults to 0 for every pre-existing row above, which would otherwise let that
 	// account skip its username change entirely once it re-hits /first-login next.
 	db.Exec(`UPDATE esrv_admin_users SET must_change_username = 1 WHERE username = ? AND must_change_password = 1`, DefaultAdminUsername)
+	migrateSpamRenamedToJunk(db)
+}
+
+// migrateSpamRenamedToJunk renames the standard "Spam" folder to "Junk" for mailboxes
+// that already had messages/records under the old name — "Junk" is what most desktop
+// IMAP clients look for by name (see db.StandardMailboxFolders' doc comment). Always
+// safe to re-run: once nothing's left named "Spam" every UPDATE here matches zero
+// rows.
+// ponytail: doesn't handle the (very unlikely) case where a mailbox already has an
+// unrelated custom folder literally named "Junk" before this rename — that one row's
+// UPDATE would fail on the UNIQUE(mailbox_id, name) constraint and get silently
+// skipped, same as every other best-effort statement in this function. Rename that
+// mailbox's pre-existing "Junk" folder first if this ever comes up in practice.
+func migrateSpamRenamedToJunk(db *sql.DB) {
+	db.Exec(`UPDATE esrv_mailbox_messages SET folder = 'Junk' WHERE folder = 'Spam'`)
+	db.Exec(`UPDATE esrv_mailbox_folders SET name = 'Junk' WHERE name = 'Spam'`)
+	db.Exec(`UPDATE esrv_mailbox_folders SET parent_root = 'Junk' WHERE parent_root = 'Spam'`)
 }
 
 // DB wraps *sql.DB with the query helpers below.

internal/imapserver/imapserver_test.go

@@ -174,7 +174,7 @@ func TestIMAPListAndSelectAdditionalFolder(t *testing.T) {
 	if _, err := store.StoreMessage(mailboxID, "INBOX", []byte("Subject: normal\r\n\r\nhi"), "<a@example.com>", "a@example.com", "normal"); err != nil {
 		t.Fatal(err)
 	}
-	if _, err := store.StoreMessage(mailboxID, "Spam", []byte("Subject: junk\r\n\r\nspam"), "<b@example.com>", "b@example.com", "junk"); err != nil {
+	if _, err := store.StoreMessage(mailboxID, "Junk", []byte("Subject: junk\r\n\r\nspam"), "<b@example.com>", "b@example.com", "junk"); err != nil {
 		t.Fatal(err)
 	}
 
@@ -201,12 +201,46 @@ func TestIMAPListAndSelectAdditionalFolder(t *testing.T) {
 	if err != nil {
 		t.Fatalf("list: %v", err)
 	}
-	var names []string
+	// LIST must report every standard folder (INBOX, Junk, Sent, Drafts, Trash) even
+	// though only INBOX and Junk actually hold a message here — a desktop client that
+	// only sees folders with existing mail never learns Trash/Drafts/Sent exist. See
+	// db.AllFoldersForMailbox / imapserver.Session.List.
+	byName := map[string]*imap.ListData{}
+	for _, m := range mailboxes {
+		byName[m.Mailbox] = m
+	}
+	wantFolders := []string{"INBOX", "Junk", "Sent", "Drafts", "Trash"}
+	if len(mailboxes) != len(wantFolders) {
+		names := make([]string, 0, len(mailboxes))
 		for _, m := range mailboxes {
 			names = append(names, m.Mailbox)
 		}
-	if len(names) != 2 {
-		t.Fatalf("expected 2 folders (INBOX, Spam), got %v", names)
+		t.Fatalf("expected folders %v, got %v", wantFolders, names)
+	}
+	for _, name := range wantFolders {
+		if _, ok := byName[name]; !ok {
+			t.Errorf("LIST is missing folder %q", name)
+		}
+	}
+	// Trash/Junk/Sent/Drafts should each carry their RFC 6154 SPECIAL-USE attribute
+	// so a desktop client (Thunderbird, Apple Mail, etc.) recognizes them regardless
+	// of the exact folder name.
+	wantAttrs := map[string]imap.MailboxAttr{
+		"Trash":  imap.MailboxAttrTrash,
+		"Junk":   imap.MailboxAttrJunk,
+		"Sent":   imap.MailboxAttrSent,
+		"Drafts": imap.MailboxAttrDrafts,
+	}
+	for name, attr := range wantAttrs {
+		found := false
+		for _, a := range byName[name].Attrs {
+			if a == attr {
+				found = true
+			}
+		}
+		if !found {
+			t.Errorf("folder %q missing SPECIAL-USE attr %q, got %v", name, attr, byName[name].Attrs)
+		}
 	}
 
 	inboxData, err := client.Select("INBOX", nil).Wait()
@@ -217,20 +251,20 @@ func TestIMAPListAndSelectAdditionalFolder(t *testing.T) {
 		t.Fatalf("INBOX NumMessages = %d, want 1", inboxData.NumMessages)
 	}
 
-	spamData, err := client.Select("Spam", nil).Wait()
+	spamData, err := client.Select("Junk", nil).Wait()
 	if err != nil {
-		t.Fatalf("select Spam: %v", err)
+		t.Fatalf("select Junk: %v", err)
 	}
 	if spamData.NumMessages != 1 {
-		t.Fatalf("Spam NumMessages = %d, want 1", spamData.NumMessages)
+		t.Fatalf("Junk NumMessages = %d, want 1", spamData.NumMessages)
 	}
 
 	msgs, err := client.Fetch(imap.SeqSetNum(1), &imap.FetchOptions{Envelope: true}).Collect()
 	if err != nil {
-		t.Fatalf("fetch in Spam: %v", err)
+		t.Fatalf("fetch in Junk: %v", err)
 	}
 	if len(msgs) != 1 || msgs[0].Envelope.Subject != "junk" {
-		t.Fatalf("expected the Spam-folder message (subject %q), got %+v", "junk", msgs)
+		t.Fatalf("expected the Junk-folder message (subject %q), got %+v", "junk", msgs)
 	}
 }
 

internal/imapserver/session.go

@@ -177,14 +177,37 @@ func (s *Session) Unsubscribe(mailbox string) error {
 	return nil
 }
 
-// List reports every folder that actually has mail (plus INBOX, always) — a filter
-// rule's move_to_folder action is what creates a second folder; there's no IMAP
-// CREATE/manual folder management.
+// specialUseAttrs tags a folder with its RFC 6154 SPECIAL-USE attribute, if any —
+// desktop IMAP clients (Thunderbird, Apple Mail, K-9, etc.) use this to recognize
+// Trash/Junk/Sent/Drafts regardless of the exact folder name, though in practice not
+// every client honors SPECIAL-USE reliably, which is why the folder itself is named
+// "Junk" (see db.StandardMailboxFolders) rather than relying on this attribute alone.
+func specialUseAttrs(folder string) []imap.MailboxAttr {
+	switch folder {
+	case "Trash":
+		return []imap.MailboxAttr{imap.MailboxAttrTrash}
+	case "Junk":
+		return []imap.MailboxAttr{imap.MailboxAttrJunk}
+	case "Sent":
+		return []imap.MailboxAttr{imap.MailboxAttrSent}
+	case "Drafts":
+		return []imap.MailboxAttr{imap.MailboxAttrDrafts}
+	default:
+		return nil
+	}
+}
+
+// List reports every folder the mailbox has: the standard folders (INBOX, Junk, Sent,
+// Drafts, Trash — always, even empty) plus any custom folder a filter rule's
+// move_to_folder action or explicit webmail folder creation has produced — the same
+// full list db.AllFoldersForMailbox gives the webmail UI, so a desktop IMAP client
+// sees exactly the same folders webmail does instead of only ones that happen to
+// already hold a message (DistinctFoldersForMailbox alone).
 func (s *Session) List(w *goimapserver.ListWriter, ref string, patterns []string, options *imap.ListOptions) error {
 	if err := s.requireAuth(); err != nil {
 		return err
 	}
-	folders, err := s.backend.DB.DistinctFoldersForMailbox(s.mailbox.ID)
+	folders, err := s.backend.DB.AllFoldersForMailbox(s.mailbox.ID)
 	if err != nil {
 		return err
 	}
@@ -199,7 +222,7 @@ func (s *Session) List(w *goimapserver.ListWriter, ref string, patterns []string
 			if !goimapserver.MatchList(folder, '/', ref, pattern) {
 				continue
 			}
-			if err := w.WriteList(&imap.ListData{Mailbox: folder, Delim: '/'}); err != nil {
+			if err := w.WriteList(&imap.ListData{Mailbox: folder, Delim: '/', Attrs: specialUseAttrs(folder)}); err != nil {
 				return err
 			}
 		}

internal/mailstore/rules.go

@@ -35,10 +35,10 @@ func (s *Store) ApplyRules(mailboxID int64, headers map[string]string) (FilterAc
 		case "move_to_folder":
 			return FilterAction{Folder: r.ActionValue}, nil
 		case "mark_as_spam":
-			// Reuses the same Spam folder score-based quarantine already delivers
+			// Reuses the same Junk folder score-based quarantine already delivers
 			// into (see smtpserver/session.go) — from the mailbox owner's
-			// perspective it's the same "goes to Spam" outcome either way.
-			return FilterAction{Folder: "Spam"}, nil
+			// perspective it's the same "goes to Junk" outcome either way.
+			return FilterAction{Folder: "Junk"}, nil
 		case "delete":
 			return FilterAction{Drop: true}, nil
 		case "mark_read":

internal/mailstore/rules_test.go

@@ -79,7 +79,7 @@ func TestApplyRulesMarkAsSpam(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	if action.Folder != "Spam" {
+	if action.Folder != "Junk" {
 		t.Fatalf("expected mark_as_spam to route into the Spam folder, got %+v", action)
 	}
 }

internal/relay/relay.go

@@ -27,7 +27,7 @@ type Result struct {
 	ErrorCode      string
 	ErrorMessage   string
 	ServerResponse string
-	// Quarantined is true for a local delivery that landed in Spam rather than INBOX.
+	// Quarantined is true for a local delivery that landed in Junk rather than INBOX.
 	// Only ever set by smtpserver's local-delivery path (always false for outbound
 	// relay results) — it's the signal Data() uses to keep this message's body in the
 	// admin log despite content-logging otherwise being off by default, so a spam/

internal/smtpserver/log_privacy_test.go

@@ -68,7 +68,7 @@ func TestEmailLogBodyKeptWhenQuarantined(t *testing.T) {
 		t.Fatalf("send: %v", err)
 	}
 
-	spamMsgs, err := backend.DB.ListMessagesInFolder(mailboxID, "Spam")
+	spamMsgs, err := backend.DB.ListMessagesInFolder(mailboxID, "Junk")
 	if err != nil {
 		t.Fatal(err)
 	}

internal/smtpserver/mailbox_rules_test.go

@@ -70,7 +70,7 @@ func TestAllowListBypassesSpamQuarantine(t *testing.T) {
 	if err := send(t); err != nil {
 		t.Fatalf("expected delivery accepted (quarantined) with a zero reject threshold and no allow-list entry, got: %v", err)
 	}
-	spamMsgs, err := backend.DB.ListMessagesInFolder(mailboxID, "Spam")
+	spamMsgs, err := backend.DB.ListMessagesInFolder(mailboxID, "Junk")
 	if err != nil || len(spamMsgs) != 1 {
 		t.Fatalf("expected 1 quarantined message in Spam, got %d (err=%v)", len(spamMsgs), err)
 	}
@@ -170,7 +170,7 @@ func TestFilterRuleMarkReadSetsSeenFlag(t *testing.T) {
 
 func TestFilterRuleMoveToFolderStoresInNamedFolder(t *testing.T) {
 	backend, mailboxID := newTestBackendWithMailbox(t)
-	if _, err := backend.DB.CreateRule(mailboxID, 0, "subject", "contains", "spam", "move_to_folder", "Spam"); err != nil {
+	if _, err := backend.DB.CreateRule(mailboxID, 0, "subject", "contains", "spam", "move_to_folder", "Junk"); err != nil {
 		t.Fatal(err)
 	}
 	addr := startTestServer(t, backend)
@@ -205,7 +205,7 @@ func TestFilterRuleMoveToFolderStoresInNamedFolder(t *testing.T) {
 	if len(inbox) != 0 {
 		t.Fatalf("expected nothing in INBOX, found %d", len(inbox))
 	}
-	spam, err := backend.DB.ListMessagesInFolder(mailboxID, "Spam")
+	spam, err := backend.DB.ListMessagesInFolder(mailboxID, "Junk")
 	if err != nil {
 		t.Fatal(err)
 	}

internal/smtpserver/mailbox_spam_test.go

@@ -58,7 +58,7 @@ func TestRspamdExplicitRejectActionStillHardRejects(t *testing.T) {
 		t.Fatal("expected delivery to be hard-rejected when rspamd's action is \"reject\"")
 	}
 	inboxMsgs, _ := backend.DB.ListMessagesInFolder(mailboxID, "INBOX")
-	spamMsgs, _ := backend.DB.ListMessagesInFolder(mailboxID, "Spam")
+	spamMsgs, _ := backend.DB.ListMessagesInFolder(mailboxID, "Junk")
 	if len(inboxMsgs) != 0 || len(spamMsgs) != 0 {
 		t.Fatalf("expected nothing stored anywhere for a hard reject, got INBOX=%d Spam=%d", len(inboxMsgs), len(spamMsgs))
 	}
@@ -78,7 +78,7 @@ func TestRspamdScoreThresholdQuarantinesInsteadOfRejecting(t *testing.T) {
 	if err := sendTestMessage(t, addr, "hi"); err != nil {
 		t.Fatalf("expected delivery accepted (quarantined), got: %v", err)
 	}
-	spamMsgs, err := backend.DB.ListMessagesInFolder(mailboxID, "Spam")
+	spamMsgs, err := backend.DB.ListMessagesInFolder(mailboxID, "Junk")
 	if err != nil || len(spamMsgs) != 1 {
 		t.Fatalf("expected 1 quarantined message in Spam, got %d (err=%v)", len(spamMsgs), err)
 	}

internal/smtpserver/session.go

@@ -368,7 +368,7 @@ func (s *Session) Data(r io.Reader) error {
 	// Privacy default: only headers (and the Subject field, logged separately below
 	// regardless) go into the admin-visible log, never the message itself — unless this
 	// sender/IP explicitly opted in via "Store Full Message Content" (storeMessage
-	// above), or the message was quarantined to Spam for at least one recipient, in
+	// above), or the message was quarantined to Junk for at least one recipient, in
 	// which case an admin genuinely needs to see it to judge a spam/abuse report. When
 	// stored, it's the *entire* raw message (not a plain-text extraction) so the log
 	// viewer can render the real HTML body, inline images, and attachments — re-parsed
@@ -447,7 +447,7 @@ func (s *Session) deliverLocally(rcpts, types []string, signedContent, messageID
 					// (DNSBL hit, greylisting, etc.) worth still hard-rejecting at
 					// SMTP time to avoid backscatter; a bare score threshold hit
 					// (from either scorer) is quarantined instead of rejected, so a
-					// false positive is recoverable from the Spam folder rather than
+					// false positive is recoverable from the Junk folder rather than
 					// silently bounced with no trace.
 					if rAction == "reject" {
 						hardReject = true
@@ -463,14 +463,14 @@ func (s *Session) deliverLocally(rcpts, types []string, signedContent, messageID
 				continue
 			}
 			if quarantine {
-				folder = "Spam"
+				folder = "Junk"
 				spamGated = true
 			}
 		}
 
 		// Filter rules organize legitimate mail the recipient already trusts arriving
 		// in their INBOX — a quarantined message skips them entirely and always lands
-		// in Spam, rather than a rule accidentally routing spam back into view.
+		// in Junk, rather than a rule accidentally routing spam back into view.
 		if !spamGated {
 			action, err := s.backend.Mailstore.ApplyRules(mbox.ID, map[string]string{"from": s.mailFrom, "to": rcpt, "subject": subject})
 			if err != nil {
@@ -503,7 +503,7 @@ func (s *Session) deliverLocally(rcpts, types []string, signedContent, messageID
 		}
 		serverResponse := "Delivered to local mailbox"
 		if spamGated {
-			serverResponse = "Quarantined to Spam folder"
+			serverResponse = "Quarantined to Junk folder"
 		}
 		results = append(results, relay.Result{Recipient: rcpt, RecipientType: types[i], Status: "success", ServerResponse: serverResponse, Quarantined: spamGated})
 	}

internal/webui/mailbox_rules_test.go

@@ -49,7 +49,7 @@ func TestAdminRulesAddMultiConditionAndRenders(t *testing.T) {
 	if !strings.Contains(body, "to contains "sales"") || !strings.Contains(body, "AND") {
 		t.Fatalf("expected the rendered condition summary to show both AND'd conditions, got: %s", body)
 	}
-	if !strings.Contains(body, "Mark as Spam") {
+	if !strings.Contains(body, "Mark as Junk") {
 		t.Fatal("expected the mark_as_spam action to render")
 	}
 }

internal/webui/render.go

@@ -86,6 +86,7 @@ func (a *App) funcMap() template.FuncMap {
 		},
 		"list":             func(items ...string) []string { return items },
 		"isStandardFolder": isStandardFolder,
+		"folderIcon":       folderIcon,
 		// emailOverallStatus mirrors the delivered/failed selectattr computation
 		// dashboard.html and logs.html both do in the Python templates.
 		"emailOverallStatus": func(recipients []db.EmailRecipientLog) string {
@@ -169,6 +170,7 @@ var standalonePages = []string{
 	"login.html", "login_mfa.html", "mfa_setup_required.html", "totp_setup.html",
 	"webmail_login.html", "webmail_login_mfa.html", "webmail_account.html", "webmail_totp_setup.html", "webmail_mfa_setup_required.html",
 	"webmail_folder.html", "webmail_message.html", "webmail_compose.html", "webmail_rules.html", "webmail_certs.html",
+	"webmail_signatures.html",
 	// A bare HTML fragment (no <html>/base.html chrome at all), fetched via JS and
 	// injected into logs.html's full-screen modal — not a page anyone navigates to
 	// directly, so it doesn't need to look like a standalone document the way the
@@ -186,6 +188,7 @@ var standalonePages = []string{
 // something that opens a popup of its own.
 var pagesWithComposeWidget = []string{
 	"webmail_folder.html", "webmail_message.html", "webmail_rules.html", "webmail_certs.html", "webmail_account.html",
+	"webmail_signatures.html",
 }
 
 func hasComposeWidget(page string) bool {

internal/webui/templates/mailbox_rules.html

@@ -37,7 +37,7 @@
                     <label class="form-label">Then</label>
                     <select class="form-select" name="action" id="rule_action">
                         <option value="move_to_folder">Move to folder</option>
-                        <option value="mark_as_spam">Mark as Spam</option>
+                        <option value="mark_as_spam">Mark as Junk</option>
                         <option value="delete">Delete</option>
                         <option value="mark_read">Mark as read</option>
                     </select>
@@ -93,7 +93,7 @@
                             <td><code>{{ruleSummary .}}</code></td>
                             <td>
                                 {{if eq .Action "move_to_folder"}}Move to <strong>{{.ActionValue}}</strong>
-                                {{else if eq .Action "mark_as_spam"}}<span class="text-warning">Mark as Spam</span>
+                                {{else if eq .Action "mark_as_spam"}}<span class="text-warning">Mark as Junk</span>
                                 {{else if eq .Action "delete"}}<span class="text-danger">Delete</span>
                                 {{else}}Mark as read{{end}}
                             </td>

internal/webui/templates/webmail_account.html

@@ -23,6 +23,7 @@
                 <button type="button" onclick="openCompose('/webmail/mail/compose')" class="btn btn-outline-light btn-sm"><i class="bi bi-pencil-square me-1"></i>Compose</button>
                 <a href="/webmail/rules" class="btn btn-outline-light btn-sm"><i class="bi bi-funnel me-1"></i>Rules</a>
                 <a href="/webmail/certs" class="btn btn-outline-light btn-sm"><i class="bi bi-shield-lock me-1"></i>Certs</a>
+                <a href="/webmail/signatures" class="btn btn-outline-light btn-sm"><i class="bi bi-pen me-1"></i>Signatures</a>
                 <form method="post" action="/webmail/logout" class="d-inline">
                     <button type="submit" class="btn btn-outline-light btn-sm"><i class="bi bi-box-arrow-right me-1"></i>Sign out</button>
                 </form>
@@ -32,7 +33,7 @@
 
     <div class="toast-container position-fixed top-0 end-0 p-3" style="z-index: 1090;">
         {{range .flashes}}
-        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true" data-bs-autohide="false">
+        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true">
             <div class="d-flex">
                 <div class="toast-body">
                     <i class="bi bi-{{if eq .Category "error"}}exclamation-triangle{{else if eq .Category "success"}}check-circle{{else}}info-circle{{end}} me-2"></i>

internal/webui/templates/webmail_certs.html

@@ -23,6 +23,7 @@
                 <button type="button" onclick="openCompose('/webmail/mail/compose')" class="btn btn-outline-light btn-sm"><i class="bi bi-pencil-square me-1"></i>Compose</button>
                 <a href="/webmail/rules" class="btn btn-outline-light btn-sm"><i class="bi bi-funnel me-1"></i>Rules</a>
                 <a href="/webmail/certs" class="btn btn-light btn-sm"><i class="bi bi-shield-lock me-1"></i>Certs</a>
+                <a href="/webmail/signatures" class="btn btn-outline-light btn-sm"><i class="bi bi-pen me-1"></i>Signatures</a>
                 <a href="/webmail/account" class="btn btn-outline-light btn-sm"><i class="bi bi-gear me-1"></i>Account</a>
                 <form method="post" action="/webmail/logout" class="d-inline">
                     <button type="submit" class="btn btn-outline-light btn-sm"><i class="bi bi-box-arrow-right me-1"></i>Sign out</button>
@@ -33,7 +34,7 @@
 
     <div class="toast-container position-fixed top-0 end-0 p-3" style="z-index: 1090;">
         {{range .flashes}}
-        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true" data-bs-autohide="false">
+        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true">
             <div class="d-flex">
                 <div class="toast-body">
                     <i class="bi bi-{{if eq .Category "error"}}exclamation-triangle{{else if eq .Category "success"}}check-circle{{else}}info-circle{{end}} me-2"></i>

internal/webui/templates/webmail_compose.html

@@ -61,7 +61,7 @@
     {{template "csrf_script" .}}
     <div class="toast-container position-fixed top-0 end-0 p-3" style="z-index: 1090;">
         {{range .flashes}}
-        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true" data-bs-autohide="false">
+        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true">
             <div class="d-flex">
                 <div class="toast-body">
                     <i class="bi bi-{{if eq .Category "error"}}exclamation-triangle{{else if eq .Category "success"}}check-circle{{else}}info-circle{{end}} me-2"></i>
@@ -83,6 +83,13 @@
             <small class="from-email" id="autosaveStatus" style="display: none;"></small>
             <button type="button" id="attachBtn" class="btn btn-outline-light btn-sm" title="Attach files"><i class="bi bi-paperclip"></i></button>
             <input type="file" id="attachment_input" name="attachments" multiple style="display: none;">
+            {{if .signatures}}
+            <select class="form-select form-select-sm" id="signatureSelect" style="width: auto;" title="Signature">
+                <option value="">No signature</option>
+                {{range .signatures}}<option value="{{.ID}}" {{if eq $.default_signature_id .ID}}selected{{end}}>{{.Name}}</option>{{end}}
+            </select>
+            {{range .signatures}}<div class="sig-data" data-sig-id="{{.ID}}" style="display: none;">{{.ContentHTML | safe}}</div>{{end}}
+            {{end}}
             <div class="ms-auto d-flex align-items-center gap-2">
                 {{if .send_as_options}}
                 <select class="form-select form-select-sm from-select" name="from">
@@ -175,18 +182,69 @@
                 ],
             },
         });
+        // Signature tracking: the signature is kept as a plain-paragraph Delta range
+        // (index/length) rather than a DOM marker div. A wrapping <div> set directly on
+        // quill.root gets silently discarded by Quill's own MutationObserver within one
+        // update cycle (it isn't a recognized block type) — confirmed live, so signature
+        // content is inserted via Quill's own clipboard API instead, which turns it into
+        // real paragraph blots that survive.
+        var sigRange = null; // {index, length} of the signature currently in the editor, or null
+
+        function insertSignature(index, html) {
+            if (!html) return null;
+            const before = quill.getLength();
+            quill.clipboard.dangerouslyPasteHTML(index, html);
+            return { index: index, length: quill.getLength() - before };
+        }
+
+        function removeSignature() {
+            if (sigRange && sigRange.length > 0) quill.deleteText(sigRange.index, sigRange.length);
+            sigRange = null;
+        }
+
         (function() {
             const seed = document.getElementById('body_html_seed');
-            if (seed && seed.innerHTML.trim()) {
-                quill.root.innerHTML = seed.innerHTML;
+            if (!seed || !seed.innerHTML.trim()) return;
+            const parsed = document.createElement('div');
+            parsed.innerHTML = seed.innerHTML;
+            const sigEl = parsed.querySelector('#mailSignatureBlock');
+            let sigHTML = '';
+            if (sigEl) {
+                sigHTML = sigEl.innerHTML;
+                sigEl.remove();
+            }
+            quill.root.innerHTML = parsed.innerHTML;
             // Reply/forward seeds start with an empty line above the quoted
             // original (see composeCursorHome, webmail_compose.go) — put the
             // cursor there so typing starts above the quote, not inside or after it.
             quill.setSelection(0, 0);
             quill.focus();
+            if (sigHTML) {
+                // The backend always inserts the signature immediately after that
+                // leading empty paragraph (index 1), before any quoted/forwarded
+                // text — see webmailComposeForm.
+                sigRange = insertSignature(1, sigHTML);
+                quill.setSelection(0, 0);
             }
         })();
 
+        // Signature picker: swaps the currently-inserted signature (tracked via
+        // sigRange above) for a different one, or removes it. Picking one when none
+        // exists yet appends it at the end of the body.
+        (function() {
+            const select = document.getElementById('signatureSelect');
+            if (!select) return;
+            const sigHTML = {};
+            document.querySelectorAll('.sig-data').forEach(function(el) { sigHTML[el.dataset.sigId] = el.innerHTML; });
+
+            select.addEventListener('change', function() {
+                const insertAt = sigRange ? sigRange.index : Math.max(0, quill.getLength() - 1);
+                removeSignature();
+                if (!select.value) return;
+                sigRange = insertSignature(insertAt, sigHTML[select.value] || '');
+            });
+        })();
+
         // Cc/Bcc start hidden (Outlook-style) unless prefilled (e.g. reply-all sets
         // Cc) — clicking a toggle reveals its row and focuses the field, same as
         // clicking "Cc"/"Bcc" in a real mail client.

internal/webui/templates/webmail_folder.html

@@ -38,18 +38,34 @@
         .msg-item { display: flex; align-items: flex-start; gap: .6rem; padding: .55rem .75rem; border-bottom: 1px solid #333; cursor: pointer; }
         .msg-item:hover { background-color: #262626; }
         .msg-item.active { background-color: #0d3860; }
+        .msg-item:has(.msg-check:checked) { background-color: #2a2f36; }
         .msg-item.unread .msg-subject { font-weight: 700; color: #fff; }
         .msg-item.unread .msg-from { font-weight: 700; color: #fff; }
         .msg-check { margin-top: .35rem; flex: 0 0 auto; }
         .msg-avatar { width: 34px; height: 34px; border-radius: 50%; background: #495057; color: #fff; display: flex; align-items: center; justify-content: center; font-size: .85rem; font-weight: 600; flex: 0 0 auto; }
         .msg-item.unread .msg-avatar { background: #0d6efd; }
         .msg-main { min-width: 0; flex: 1 1 auto; }
-        .msg-row1 { display: flex; justify-content: space-between; gap: .5rem; }
+        .msg-row1 { display: flex; align-items: center; gap: .4rem; }
         .msg-from { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
-        .msg-date { flex: 0 0 auto; font-size: .75rem; color: #8a8a8a; }
+        .msg-star { flex: 0 0 auto; cursor: pointer; color: #6a6a6a; }
+        .msg-star.bi-star-fill { color: #f4c150; }
+        .msg-star:hover { color: #f4c150; }
+        .msg-date { flex: 0 0 auto; font-size: .75rem; color: #8a8a8a; margin-left: auto; }
         .msg-row2 { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; font-size: .85rem; color: #adb5bd; }
         .msg-subject { color: #e0e0e0; }
 
+        #folderContextMenu { z-index: 1085; }
+        .folder-row { display: flex; align-items: center; }
+        .folder-drag-handle { cursor: grab; color: #6a6a6a; padding: 0 .25rem 0 0; flex: 0 0 auto; }
+        .folder-drag-handle:hover { color: #adb5bd; }
+        .folder-row.folder-row-dragging { opacity: 0.4; }
+        .folder-expand-toggle { flex: 0 0 auto; width: 16px; text-align: center; cursor: pointer; color: #8a8a8a; font-size: .8rem; transition: transform .1s; }
+        .folder-expand-toggle:hover { color: #fff; }
+        .folder-expand-toggle.collapsed { transform: rotate(-90deg); }
+        .folder-expand-spacer { flex: 0 0 auto; width: 16px; }
+        .folder-children { margin-left: 16px; }
+        .folder-children.collapsed { display: none; }
+
         .msg-body-html { background-color: #fff; color: #000; border-radius: 6px; padding: 1rem; overflow-x: auto; }
         .msg-body-text { white-space: pre-wrap; word-break: break-word; }
         #readingPaneBody .pane-toolbar { border-bottom: 1px solid #404040; padding-bottom: .75rem; }
@@ -69,6 +85,7 @@
             <button type="button" onclick="openCompose('/webmail/mail/compose')" class="btn btn-primary btn-sm"><i class="bi bi-pencil-square me-1"></i>Compose</button>
             <a href="/webmail/rules" class="btn btn-outline-light btn-sm" title="Rules"><i class="bi bi-funnel"></i></a>
             <a href="/webmail/certs" class="btn btn-outline-light btn-sm" title="Certs"><i class="bi bi-shield-lock"></i></a>
+            <a href="/webmail/signatures" class="btn btn-outline-light btn-sm" title="Signatures"><i class="bi bi-pen"></i></a>
             <a href="/webmail/account" class="btn btn-outline-light btn-sm" title="Account"><i class="bi bi-gear"></i></a>
             <form method="post" action="/webmail/logout" class="d-inline">
                 <button type="submit" class="btn btn-outline-light btn-sm" title="Sign out"><i class="bi bi-box-arrow-right"></i></button>
@@ -78,7 +95,7 @@
 
     <div class="toast-container position-fixed top-0 end-0 p-3" style="z-index: 1090;">
         {{range .flashes}}
-        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true" data-bs-autohide="false">
+        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true">
             <div class="d-flex">
                 <div class="toast-body">
                     <i class="bi bi-{{if eq .Category "error"}}exclamation-triangle{{else if eq .Category "success"}}check-circle{{else}}info-circle{{end}} me-2"></i>
@@ -94,37 +111,30 @@
         <div class="mail-sidebar" id="folderSidebarCol">
             <div class="d-flex justify-content-between align-items-center mb-2">
                 <span class="text-muted small text-uppercase">Folders</span>
+                <div>
+                    <button type="button" class="btn btn-sm btn-outline-secondary border-0 py-0 px-1" id="expandAllBtn" title="Expand all"><i class="bi bi-arrows-expand"></i></button>
+                    <button type="button" class="btn btn-sm btn-outline-secondary border-0 py-0 px-1" id="collapseAllBtn" title="Collapse all"><i class="bi bi-arrows-collapse"></i></button>
                     <button type="button" class="btn btn-sm btn-outline-secondary border-0 py-0" id="sidebarCollapseBtn" title="Hide folder list"><i class="bi bi-chevron-bar-left"></i></button>
                 </div>
-            <div class="list-group list-group-flush">
-                {{$active := .active_folder}}
-                {{$unread := .unread_counts}}
-                {{$counts := .folder_counts}}
-                {{range .folders}}
-                <div class="d-flex align-items-center folder-row">
-                    <a href="/webmail/mail/{{.}}" data-folder="{{.}}" class="list-group-item list-group-item-action bg-transparent text-white folder-link flex-grow-1 d-flex justify-content-between align-items-center {{if eq . $active}}active{{end}}">
-                        <span><i class="bi bi-folder2 me-1"></i>{{.}}</span>
-                        {{$n := index $unread .}}
-                        {{$total := index $counts .}}
-                        {{if $total}}
-                        <span class="badge {{if $n}}bg-primary{{else}}bg-secondary{{end}} rounded-pill folder-unread-badge" title="{{$total}} total{{if $n}}, {{$n}} unread{{end}}">{{$total}}{{if $n}} / <strong>{{$n}}</strong>{{end}}</span>
-                        {{end}}
-                    </a>
-                    {{if not (isStandardFolder .)}}
-                    <form method="post" action="/webmail/mail/folders/{{.}}/remove" class="d-inline">
-                        <button type="submit" class="btn btn-sm btn-outline-danger border-0" title="Remove folder" data-confirm="Remove folder &quot;{{.}}&quot;? Any mail in it moves to INBOX."><i class="bi bi-x-lg"></i></button>
-                    </form>
-                    {{end}}
             </div>
-                {{end}}
+            <div class="list-group list-group-flush" id="folderList">
+                {{range .folder_tree}}{{template "folderTreeNode" .}}{{end}}
             </div>
-            <hr class="my-2">
-            <form method="post" action="/webmail/mail/folders/add" class="d-flex gap-1">
-                <input type="text" class="form-control form-control-sm" name="name" placeholder="New folder" maxlength="60" required>
-                <button type="submit" class="btn btn-sm btn-outline-primary" title="Create folder"><i class="bi bi-plus-lg"></i></button>
-            </form>
+            <div class="text-muted small mt-2" style="font-size: .72rem;">Right-click a folder for more actions</div>
         </div>
 
+        <div id="folderContextMenu" class="dropdown-menu" style="display: none; position: fixed;">
+            <button type="button" class="dropdown-item" data-menu-action="new"><i class="bi bi-folder-plus me-2"></i>New folder</button>
+            <button type="button" class="dropdown-item" data-menu-action="mark-all-read"><i class="bi bi-envelope-open me-2"></i>Mark all as read</button>
+            <button type="button" class="dropdown-item" data-menu-action="rename"><i class="bi bi-pencil me-2"></i>Rename</button>
+            <button type="button" class="dropdown-item text-danger" data-menu-action="empty-trash"><i class="bi bi-trash3 me-2"></i>Empty Trash</button>
+            <button type="button" class="dropdown-item text-danger" data-menu-action="clean-spam"><i class="bi bi-shield-x me-2"></i>Clean up Junk</button>
+            <button type="button" class="dropdown-item" data-menu-action="restore-folder"><i class="bi bi-arrow-counterclockwise me-2"></i>Restore</button>
+            <button type="button" class="dropdown-item text-danger" data-menu-action="delete-folder-permanently"><i class="bi bi-trash3-fill me-2"></i>Delete permanently</button>
+        </div>
+
+        <form method="post" id="folderActionForm" class="d-none"></form>
+
         <div class="mail-list-pane{{if .search_query}} search-mode{{end}}" id="messageListCol">
             <div class="mail-toolbar">
                 <button type="button" class="btn btn-sm btn-outline-secondary border-0 py-0 d-none" id="sidebarShowBtn" title="Show folder list"><i class="bi bi-chevron-bar-right"></i></button>
@@ -147,6 +157,7 @@
                     <a href="{{.sort_from_href}}" class="btn btn-sm btn-outline-secondary border-0 py-0" title="Sort by sender"><i class="bi bi-person{{if eq .sort_by "from"}}-fill{{end}}"></i>{{if eq .sort_by "from"}} <i class="bi bi-caret-{{if eq .sort_dir "asc"}}up{{else}}down{{end}}-fill"></i>{{end}}</a>
                     <a href="{{.sort_date_href}}" class="btn btn-sm btn-outline-secondary border-0 py-0" title="Sort by date"><i class="bi bi-calendar3{{if ne .sort_by "from"}}-fill{{end}}"></i>{{if ne .sort_by "from"}} <i class="bi bi-caret-{{if eq .sort_dir "asc"}}up{{else}}down{{end}}-fill"></i>{{end}}</a>
                     <a href="{{.unread_only_href}}" class="btn btn-sm border-0 py-0 {{if .unread_only}}btn-primary{{else}}btn-outline-secondary{{end}}" title="Unread only"><i class="bi bi-envelope-fill"></i></a>
+                    <a href="{{.starred_only_href}}" class="btn btn-sm border-0 py-0 {{if .starred_only}}btn-warning{{else}}btn-outline-secondary{{end}}" title="Favourites only"><i class="bi bi-star-fill"></i></a>
                     {{end}}
                 </div>
             </div>
@@ -169,6 +180,7 @@
                         <div class="msg-main">
                             <div class="msg-row1">
                                 <span class="msg-from" title="{{if eq .Folder "Sent"}}{{.CachedTo}}{{else}}{{.CachedFrom}}{{end}}">{{$displayName}}</span>
+                                <i class="bi msg-star {{if .Starred}}bi-star-fill{{else}}bi-star{{end}}" data-uid="{{.ID}}" data-folder="{{.Folder}}" title="{{if .Starred}}Remove from favourites{{else}}Add to favourites{{end}}"></i>
                                 <span class="msg-date">{{strftime "%Y-%m-%d %H:%M" .InternalDate}}</span>
                             </div>
                             <div class="msg-row2">
@@ -223,6 +235,26 @@
         </div>
     </div>
 
+    <div class="modal fade" id="inputModal" tabindex="-1" aria-hidden="true">
+        <div class="modal-dialog">
+            <div class="modal-content">
+                <form id="inputModalForm">
+                    <div class="modal-header">
+                        <h5 class="modal-title" id="inputModalTitle"><i class="bi bi-pencil me-2"></i>Folder name</h5>
+                        <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
+                    </div>
+                    <div class="modal-body">
+                        <input type="text" class="form-control" id="inputModalField" maxlength="60" required>
+                    </div>
+                    <div class="modal-footer">
+                        <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Cancel</button>
+                        <button type="submit" class="btn btn-primary" id="inputModalConfirm">OK</button>
+                    </div>
+                </form>
+            </div>
+        </div>
+    </div>
+
     {{template "compose_widget" .}}
     {{template "webmail_shortcuts" .}}
 
@@ -247,17 +279,53 @@
                 new bootstrap.Modal(modal).show();
             });
         }
-        document.addEventListener('DOMContentLoaded', function() {
-            document.querySelectorAll('[data-confirm]').forEach(function(button) {
-                button.addEventListener('click', async function(e) {
+        // showInputPrompt replaces the browser's native prompt() for folder
+        // name/rename input — a native prompt() blocks the whole tab (including any
+        // in-flight automation/extension driving it) until dismissed, and looks/feels
+        // inconsistent with the confirm dialog above. Resolves the entered text, or
+        // null if cancelled — same null-on-cancel contract prompt() itself has.
+        function showInputPrompt(title, defaultValue) {
+            return new Promise((resolve) => {
+                const modal = document.getElementById('inputModal');
+                const form = document.getElementById('inputModalForm');
+                const field = document.getElementById('inputModalField');
+                document.getElementById('inputModalTitle').textContent = title;
+                field.value = defaultValue || '';
+                let resolved = false;
+                const handleSubmit = (e) => {
                     e.preventDefault();
-                    if (await showConfirmation(this.getAttribute('data-confirm'))) {
-                        const form = this.closest('form');
+                    resolved = true;
+                    resolve(field.value.trim());
+                    bootstrap.Modal.getInstance(modal).hide();
+                    cleanup();
+                };
+                const handleCancel = () => {
+                    if (!resolved) resolve(null);
+                    cleanup();
+                };
+                const cleanup = () => {
+                    form.removeEventListener('submit', handleSubmit);
+                    modal.removeEventListener('hidden.bs.modal', handleCancel);
+                };
+                form.addEventListener('submit', handleSubmit);
+                modal.addEventListener('hidden.bs.modal', handleCancel, { once: true });
+                new bootstrap.Modal(modal).show();
+                modal.addEventListener('shown.bs.modal', function() { field.focus(); field.select(); }, { once: true });
+            });
+        }
+        // Delegated (not per-element) so this also covers [data-confirm] buttons
+        // injected later via fetch — the reading pane's own delete button, loaded
+        // into #readingPaneBody by openInPane, wouldn't exist yet at DOMContentLoaded
+        // time for a per-element listener to attach to.
+        document.addEventListener('click', async function(e) {
+            const button = e.target.closest('[data-confirm]');
+            if (!button) return;
+            e.preventDefault();
+            if (await showConfirmation(button.getAttribute('data-confirm'))) {
+                const form = button.closest('form');
                 if (form) form.submit();
             }
         });
-            });
-        });
 
         // Drag a message row onto a folder in the sidebar to move it there — a
         // shortcut for the toolbar's "Move to..." control. Each row carries its OWN
@@ -305,6 +373,114 @@
             });
         })();
 
+        // Drag-and-drop folder reordering — root folders (INBOX/Junk/Sent/Drafts/
+        // Trash) are static and never draggable; only a custom folder still under
+        // INBOX (server-computed .Renameable — see buildFolderView) can be dragged,
+        // and only among its OWN siblings (rows sharing the same immediate .folder-
+        // children parent — dragging never re-parents a folder, only reorders it
+        // where it already is). A dragged row's own .folder-children (if it has
+        // descendants) moves right along with it, or its whole subtree would get
+        // visually orphaned mid-drag. Reorders the DOM live as you drag (move the
+        // dragged row to whichever side of the row under the cursor it's closer to —
+        // a common no-library technique), persisting just that sibling group's final
+        // order once on dragend. draggingRow being set is what keeps this from firing
+        // during the unrelated "drag a message onto a folder" drag above (that one's
+        // own dragover guard checks draggedUID instead, so the two never interfere).
+        (function() {
+            const list = document.getElementById('folderList');
+            if (!list) return;
+            let draggingRow = null;
+            let draggingChildren = null;
+
+            function persistOrder(parentEl) {
+                const order = Array.from(parentEl.children)
+                    .filter(function(el) { return el.classList.contains('folder-row'); })
+                    .map(function(el) { return el.dataset.folder; });
+                const body = new URLSearchParams();
+                order.forEach(function(name) { body.append('order', name); });
+                body.set('csrf_token', window.__csrfToken || '');
+                fetch('/webmail/mail/folders/order', {
+                    method: 'POST',
+                    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
+                    body: body.toString(),
+                });
+            }
+
+            list.querySelectorAll('.folder-row[draggable="true"]').forEach(function(row) {
+                row.addEventListener('dragstart', function(e) {
+                    e.stopPropagation();
+                    draggingRow = row;
+                    draggingChildren = row.nextElementSibling && row.nextElementSibling.classList.contains('folder-children')
+                        ? row.nextElementSibling : null;
+                    row.classList.add('folder-row-dragging');
+                });
+                row.addEventListener('dragend', function() {
+                    row.classList.remove('folder-row-dragging');
+                    if (draggingRow) persistOrder(draggingRow.parentElement);
+                    draggingRow = null;
+                    draggingChildren = null;
+                });
+                row.addEventListener('dragover', function(e) {
+                    if (!draggingRow || draggingRow === row) return;
+                    if (draggingRow.parentElement !== row.parentElement) return; // reorder only, never re-parent
+                    e.preventDefault();
+                    e.stopPropagation();
+                    const rect = row.getBoundingClientRect();
+                    const before = (e.clientY - rect.top) < rect.height / 2;
+                    row.parentNode.insertBefore(draggingRow, before ? row : row.nextSibling);
+                    if (draggingChildren) row.parentNode.insertBefore(draggingChildren, draggingRow.nextSibling);
+                });
+            });
+        })();
+
+        // Folder tree expand/collapse — a display preference remembered per-browser
+        // (localStorage, a Set of collapsed folder names), same pattern as the
+        // sidebar-hide toggle below. Default is fully expanded (nothing collapsed).
+        (function() {
+            const KEY = 'webmail_collapsed_folders';
+            function loadCollapsed() {
+                try { return new Set(JSON.parse(localStorage.getItem(KEY)) || []); } catch (e) { return new Set(); }
+            }
+            function saveCollapsed(set) { localStorage.setItem(KEY, JSON.stringify(Array.from(set))); }
+
+            function setCollapsed(name, collapsed) {
+                const toggle = document.querySelector('[data-folder-toggle="' + CSS.escape(name) + '"]');
+                const kids = document.querySelector('[data-children-of="' + CSS.escape(name) + '"]');
+                if (toggle) { toggle.classList.toggle('collapsed', collapsed); toggle.title = collapsed ? 'Expand' : 'Collapse'; }
+                if (kids) kids.classList.toggle('collapsed', collapsed);
+            }
+
+            const collapsed = loadCollapsed();
+            collapsed.forEach(function(name) { setCollapsed(name, true); });
+
+            document.querySelectorAll('.folder-expand-toggle').forEach(function(toggle) {
+                toggle.addEventListener('click', function(e) {
+                    e.preventDefault();
+                    e.stopPropagation();
+                    const name = toggle.dataset.folderToggle;
+                    const nowCollapsed = !toggle.classList.contains('collapsed');
+                    setCollapsed(name, nowCollapsed);
+                    if (nowCollapsed) collapsed.add(name); else collapsed.delete(name);
+                    saveCollapsed(collapsed);
+                });
+            });
+
+            const expandAllBtn = document.getElementById('expandAllBtn');
+            const collapseAllBtn = document.getElementById('collapseAllBtn');
+            if (expandAllBtn) expandAllBtn.addEventListener('click', function() {
+                document.querySelectorAll('[data-folder-toggle]').forEach(function(t) { setCollapsed(t.dataset.folderToggle, false); });
+                collapsed.clear();
+                saveCollapsed(collapsed);
+            });
+            if (collapseAllBtn) collapseAllBtn.addEventListener('click', function() {
+                document.querySelectorAll('[data-folder-toggle]').forEach(function(t) {
+                    setCollapsed(t.dataset.folderToggle, true);
+                    collapsed.add(t.dataset.folderToggle);
+                });
+                saveCollapsed(collapsed);
+            });
+        })();
+
         // "+N more" toggle for a collapsed same-subject run — reveals every
         // immediately-following row marked as part of that group, self-terminating
         // at the first row that isn't (no need to track the count client-side).
@@ -343,37 +519,21 @@
             });
         })();
 
-        // Reading pane: clicking a row loads the message via fetch instead of
-        // navigating away, mirroring the admin dashboard's message-log modal. Drafts
-        // still navigate to compose (there's nothing to "read"). The clicked row is
-        // marked read optimistically client-side — the pane fetch itself is what
-        // actually marks it read server-side (see webmailMessagePane).
+        // Reading pane + selection share one block because Shift/Ctrl-click needs to
+        // work when clicking anywhere on a row, not just its small checkbox — a plain
+        // click opens the message in the reading pane; Shift-click range-selects from
+        // the last row you interacted with (open or select) to this one; Ctrl/Cmd-click
+        // toggles just this row. Any of those needs the full row list + index, not just
+        // the checkbox's own click event, so it can't be two independent IIFEs the way
+        // "load the pane" and "manage checkboxes" would otherwise naturally split.
         (function() {
             const paneBody = document.getElementById('readingPaneBody');
-            document.querySelectorAll('.msg-item').forEach(function(row) {
-                row.addEventListener('click', function(e) {
-                    if (e.target.closest('.msg-group-toggle') || e.target.classList.contains('msg-check')) return;
-                    if (row.dataset.isDraft === 'true') { window.location.href = row.dataset.href; return; }
-                    document.querySelectorAll('.msg-item.active').forEach(function(r) { r.classList.remove('active'); });
-                    row.classList.add('active');
-                    row.classList.remove('unread');
-                    paneBody.innerHTML = '<div class="text-center text-muted py-5"><div class="spinner-border" role="status"></div></div>';
-                    fetch(row.dataset.paneHref)
-                        .then(function(r) { if (!r.ok) throw new Error(r.status); return r.text(); })
-                        .then(function(html) { paneBody.innerHTML = html; })
-                        .catch(function() { paneBody.innerHTML = '<p class="text-danger">Failed to load the message.</p>'; });
-                });
-            });
-        })();
-
-        // Selection (checkboxes + select-all + Shift-click range) driving the bulk
-        // toolbar buttons — enabled only once something's actually selected.
-        (function() {
-            const checks = Array.from(document.querySelectorAll('.msg-check'));
+            const rows = Array.from(document.querySelectorAll('.msg-item'));
+            const checks = rows.map(function(row) { return row.querySelector('.msg-check'); });
             const selectAll = document.getElementById('selectAllCheck');
             const bulkBtns = document.querySelectorAll('.bulk-btn');
             const moveSelect = document.getElementById('bulkMoveSelect');
-            let lastCheckedIndex = null;
+            let lastIndex = null;
 
             function updateToolbar() {
                 const any = checks.some(function(c) { return c.checked; });
@@ -382,13 +542,48 @@
                 selectAll.checked = checks.length > 0 && checks.every(function(c) { return c.checked; });
             }
 
+            function openInPane(row) {
+                if (row.dataset.isDraft === 'true') { window.location.href = row.dataset.href; return; }
+                rows.forEach(function(r) { r.classList.remove('active'); });
+                row.classList.add('active');
+                row.classList.remove('unread');
+                paneBody.innerHTML = '<div class="text-center text-muted py-5"><div class="spinner-border" role="status"></div></div>';
+                fetch(row.dataset.paneHref)
+                    .then(function(r) { if (!r.ok) throw new Error(r.status); return r.text(); })
+                    .then(function(html) { paneBody.innerHTML = html; })
+                    .catch(function() { paneBody.innerHTML = '<p class="text-danger">Failed to load the message.</p>'; });
+            }
+
+            rows.forEach(function(row, i) {
+                row.addEventListener('click', function(e) {
+                    if (e.target.closest('.msg-group-toggle') || e.target.classList.contains('msg-check')) return;
+
+                    if (e.shiftKey && lastIndex !== null) {
+                        e.preventDefault();
+                        const [from, to] = [lastIndex, i].sort(function(a, b) { return a - b; });
+                        for (let j = from; j <= to; j++) checks[j].checked = true;
+                        updateToolbar();
+                        return;
+                    }
+                    if (e.ctrlKey || e.metaKey) {
+                        e.preventDefault();
+                        checks[i].checked = !checks[i].checked;
+                        lastIndex = i;
+                        updateToolbar();
+                        return;
+                    }
+                    lastIndex = i;
+                    openInPane(row);
+                });
+            });
+
             checks.forEach(function(cb, i) {
                 cb.addEventListener('click', function(e) {
-                    if (e.shiftKey && lastCheckedIndex !== null) {
-                        const [from, to] = [lastCheckedIndex, i].sort(function(a, b) { return a - b; });
+                    if (e.shiftKey && lastIndex !== null) {
+                        const [from, to] = [lastIndex, i].sort(function(a, b) { return a - b; });
                         for (let j = from; j <= to; j++) checks[j].checked = cb.checked;
                     }
-                    lastCheckedIndex = i;
+                    lastIndex = i;
                     updateToolbar();
                 });
             });
@@ -437,7 +632,162 @@
                 });
             }
         })();
+
+        // Star toggle — click the star icon to flip \Flagged (see
+        // db.ToggleMessageStarred) without a full page reload. stopPropagation keeps
+        // this from also triggering the row's own click (which would open the reading
+        // pane / range-select, see the combined IIFE above).
+        document.querySelectorAll('.msg-star').forEach(function(star) {
+            star.addEventListener('click', async function(e) {
+                e.stopPropagation();
+                const uid = star.dataset.uid, folder = star.dataset.folder;
+                const body = new URLSearchParams();
+                body.set('csrf_token', window.__csrfToken || '');
+                const resp = await fetch(`/webmail/mail/${folder}/${uid}/star`, {
+                    method: 'POST',
+                    headers: { 'Content-Type': 'application/x-www-form-urlencoded' },
+                    body: body.toString(),
+                });
+                if (!resp.ok) return;
+                const nowStarred = star.classList.toggle('bi-star-fill');
+                star.classList.toggle('bi-star', !nowStarred);
+                star.title = nowStarred ? 'Remove from favourites' : 'Add to favourites';
+            });
+        });
+
+        // Folder sidebar context menu — right-click any folder for New folder / Mark
+        // all as read / Rename / Empty Trash, replacing the old always-visible "+ New
+        // folder" form. Every action posts through #folderActionForm (shared, its
+        // action/fields set right before submit) rather than one form per action, same
+        // reasoning as the message list's #bulkActionForm.
+        (function() {
+            const menu = document.getElementById('folderContextMenu');
+            const form = document.getElementById('folderActionForm');
+            let menuFolder = null;
+
+            // fields is a plain {name: value} object — each key becomes a hidden
+            // input, replacing whatever the previous action left behind.
+            function postAction(url, fields) {
+                form.action = url;
+                form.querySelectorAll('input[data-dynamic]').forEach(function(el) { el.remove(); });
+                const all = Object.assign({ csrf_token: window.__csrfToken || '' }, fields || {});
+                Object.keys(all).forEach(function(name) {
+                    const input = document.createElement('input');
+                    input.type = 'hidden'; input.name = name; input.value = all[name];
+                    input.dataset.dynamic = '1';
+                    form.appendChild(input);
+                });
+                form.submit();
+            }
+
+            function hideMenu() { menu.style.display = 'none'; menuFolder = null; }
+
+            document.querySelectorAll('.folder-row').forEach(function(row) {
+                row.addEventListener('contextmenu', function(e) {
+                    e.preventDefault();
+                    menuFolder = row.dataset.folder;
+                    const renameable = row.dataset.renameable === 'true';
+                    const isTrash = row.dataset.trash === 'true';
+                    const isSpam = row.dataset.spam === 'true';
+                    const underTrash = row.dataset.underTrash === 'true';
+                    const canAddSubfolder = row.dataset.canAddSubfolder === 'true';
+                    menu.querySelector('[data-menu-action="new"]').style.display = canAddSubfolder ? '' : 'none';
+                    menu.querySelector('[data-menu-action="rename"]').style.display = renameable ? '' : 'none';
+                    menu.querySelector('[data-menu-action="empty-trash"]').style.display = isTrash ? '' : 'none';
+                    menu.querySelector('[data-menu-action="clean-spam"]').style.display = isSpam ? '' : 'none';
+                    menu.querySelector('[data-menu-action="restore-folder"]').style.display = underTrash ? '' : 'none';
+                    menu.querySelector('[data-menu-action="delete-folder-permanently"]').style.display = underTrash ? '' : 'none';
+                    menu.style.left = e.clientX + 'px';
+                    menu.style.top = e.clientY + 'px';
+                    menu.style.display = 'block';
+                });
+            });
+
+            menu.querySelectorAll('[data-menu-action]').forEach(function(item) {
+                item.addEventListener('click', async function() {
+                    const folder = menuFolder;
+                    const action = item.dataset.menuAction;
+                    hideMenu();
+                    if (!folder) return;
+                    switch (action) {
+                        case 'new': {
+                            const name = await showInputPrompt('New folder name (inside "' + folder + '")');
+                            if (name) postAction('/webmail/mail/folders/add', { name: name, parent: folder });
+                            break;
+                        }
+                        case 'mark-all-read':
+                            postAction(`/webmail/mail/${folder}/mark-all-read`);
+                            break;
+                        case 'rename': {
+                            const name = await showInputPrompt('Rename "' + folder + '" to', folder);
+                            if (name && name !== folder) {
+                                postAction(`/webmail/mail/folders/${folder}/rename`, { new_name: name });
+                            }
+                            break;
+                        }
+                        case 'empty-trash':
+                            if (await showConfirmation('Permanently delete every message in Trash (and any folder deleted into it)? This can\'t be undone.')) {
+                                postAction(`/webmail/mail/${folder}/empty`);
+                            }
+                            break;
+                        case 'clean-spam':
+                            if (await showConfirmation('Permanently delete every message in Junk? This can\'t be undone — they will NOT be moved to Trash.')) {
+                                postAction(`/webmail/mail/${folder}/clean-spam`);
+                            }
+                            break;
+                        case 'restore-folder':
+                            postAction(`/webmail/mail/folders/${folder}/restore`);
+                            break;
+                        case 'delete-folder-permanently':
+                            if (await showConfirmation('Permanently delete folder "' + folder + '" (and anything nested inside it)? This can\'t be undone.')) {
+                                postAction(`/webmail/mail/folders/${folder}/delete-permanently`);
+                            }
+                            break;
+                    }
+                });
+            });
+
+            document.addEventListener('click', function(e) {
+                if (!menu.contains(e.target)) hideMenu();
+            });
+            document.addEventListener('keydown', function(e) {
+                if (e.key === 'Escape') hideMenu();
+            });
+            window.addEventListener('scroll', hideMenu, true);
+        })();
     </script>
 </body>
 </html>
 {{end}}
+
+{{/* folderTreeNode renders one sidebar folder row plus (if any) its children,
+     recursing into itself for each child — . is a *folderViewNode (webmail_mail.go's
+     buildFolderView), which carries everything needed (icon, counts, active state,
+     renameable/can-add-child/is-spam/is-trash) precomputed, so no shared state needs
+     threading through the recursion beyond the node itself. */}}
+{{define "folderTreeNode"}}
+<div class="folder-row {{if .Children}}folder-has-children{{end}}" data-folder="{{.Name}}" data-renameable="{{.Renameable}}" data-can-add-subfolder="{{.CanAddKid}}" data-trash="{{.IsTrash}}" data-spam="{{.IsSpam}}" data-under-trash="{{.UnderTrash}}"{{if .Renameable}} draggable="true"{{end}}>
+    {{if .Children}}
+    <i class="bi bi-chevron-down folder-expand-toggle" data-folder-toggle="{{.Name}}" title="Collapse"></i>
+    {{else}}
+    <span class="folder-expand-spacer"></span>
+    {{end}}
+    {{if .Renameable}}<i class="bi bi-grip-vertical folder-drag-handle" title="Drag to reorder"></i>{{end}}
+    <a href="/webmail/mail/{{.Name}}" data-folder="{{.Name}}" draggable="false" class="list-group-item list-group-item-action bg-transparent text-white folder-link flex-grow-1 d-flex justify-content-between align-items-center {{if .Active}}active{{end}}">
+        <span>{{if isStandardFolder .Name}}<i class="bi {{.Icon}} me-1"></i>{{end}}{{.Name}}</span>
+        {{if .Total}}
+        <span class="badge {{if .Unread}}bg-primary{{else}}bg-secondary{{end}} rounded-pill folder-unread-badge" title="{{.Total}} total{{if .Unread}}, {{.Unread}} unread{{end}}">{{.Total}}{{if .Unread}} / <strong>{{.Unread}}</strong>{{end}}</span>
+        {{end}}
+    </a>
+    {{if .Renameable}}
+    <form method="post" action="/webmail/mail/folders/{{.Name}}/remove" class="d-inline">
+        <button type="submit" class="btn btn-sm btn-outline-danger border-0" title="Delete folder" data-confirm="Delete folder &quot;{{.Name}}&quot;? Any mail in it moves to Trash, keeping this folder as a subfolder there so you can find it."><i class="bi bi-x-lg"></i></button>
+    </form>
+    {{end}}
+</div>
+{{if .Children}}
+<div class="folder-children" data-children-of="{{.Name}}">
+    {{range .Children}}{{template "folderTreeNode" .}}{{end}}
+</div>
+{{end}}
+{{end}}

internal/webui/templates/webmail_message.html

@@ -24,6 +24,7 @@
                 <button type="button" onclick="openCompose('/webmail/mail/compose')" class="btn btn-outline-light btn-sm"><i class="bi bi-pencil-square me-1"></i>Compose</button>
                 <a href="/webmail/rules" class="btn btn-outline-light btn-sm"><i class="bi bi-funnel me-1"></i>Rules</a>
                 <a href="/webmail/certs" class="btn btn-outline-light btn-sm"><i class="bi bi-shield-lock me-1"></i>Certs</a>
+                <a href="/webmail/signatures" class="btn btn-outline-light btn-sm"><i class="bi bi-pen me-1"></i>Signatures</a>
                 <a href="/webmail/account" class="btn btn-outline-light btn-sm"><i class="bi bi-gear me-1"></i>Account</a>
                 <form method="post" action="/webmail/logout" class="d-inline">
                     <button type="submit" class="btn btn-outline-light btn-sm"><i class="bi bi-box-arrow-right me-1"></i>Sign out</button>
@@ -34,7 +35,7 @@
 
     <div class="toast-container position-fixed top-0 end-0 p-3" style="z-index: 1090;">
         {{range .flashes}}
-        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true" data-bs-autohide="false">
+        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true">
             <div class="d-flex">
                 <div class="toast-body">
                     <i class="bi bi-{{if eq .Category "error"}}exclamation-triangle{{else if eq .Category "success"}}check-circle{{else}}info-circle{{end}} me-2"></i>
@@ -137,8 +138,13 @@
                     </select>
                     <button type="submit" class="btn btn-outline-secondary btn-sm">Move</button>
                 </form>
+                {{if .under_trash}}
+                <form method="post" action="/webmail/mail/{{.active_folder}}/{{.uid}}/restore">
+                    <button type="submit" class="btn btn-outline-secondary btn-sm"><i class="bi bi-arrow-counterclockwise me-1"></i>Restore</button>
+                </form>
+                {{end}}
                 <form method="post" action="/webmail/mail/{{.active_folder}}/{{.uid}}/delete">
-                    <button type="submit" class="btn btn-outline-danger btn-sm" data-confirm="{{if eq .active_folder "Trash"}}Permanently delete this message? This cannot be undone.{{else}}Move this message to Trash?{{end}}"><i class="bi bi-trash me-1"></i>{{if eq .active_folder "Trash"}}Delete Permanently{{else}}Move to Trash{{end}}</button>
+                    <button type="submit" class="btn btn-outline-danger btn-sm" data-confirm="{{if .under_trash}}Permanently delete this message? This cannot be undone.{{else}}Move this message to Trash?{{end}}"><i class="bi bi-trash me-1"></i>{{if .under_trash}}Delete Permanently{{else}}Move to Trash{{end}}</button>
                 </form>
             </div>
         </div>

internal/webui/templates/webmail_message_pane.html

@@ -15,9 +15,15 @@
             </select>
             <button type="submit" class="btn btn-outline-secondary btn-sm" title="Move"><i class="bi bi-folder-symlink"></i></button>
         </form>
-        <form method="post" action="/webmail/mail/{{.active_folder}}/{{.uid}}/delete" onsubmit="return confirm('{{if eq .active_folder "Trash"}}Permanently delete this message? This cannot be undone.{{else}}Move this message to Trash?{{end}}');">
+        {{if .under_trash}}
+        <form method="post" action="/webmail/mail/{{.active_folder}}/{{.uid}}/restore">
             <input type="hidden" name="csrf_token" value="{{.csrf_token}}">
-            <button type="submit" class="btn btn-outline-danger btn-sm" title="{{if eq .active_folder "Trash"}}Delete Permanently{{else}}Move to Trash{{end}}"><i class="bi bi-trash"></i></button>
+            <button type="submit" class="btn btn-outline-secondary btn-sm" title="Restore"><i class="bi bi-arrow-counterclockwise"></i></button>
+        </form>
+        {{end}}
+        <form method="post" action="/webmail/mail/{{.active_folder}}/{{.uid}}/delete" data-confirm="{{if .under_trash}}Permanently delete this message? This cannot be undone.{{else}}Move this message to Trash?{{end}}">
+            <input type="hidden" name="csrf_token" value="{{.csrf_token}}">
+            <button type="submit" class="btn btn-outline-danger btn-sm" title="{{if .under_trash}}Delete Permanently{{else}}Move to Trash{{end}}"><i class="bi bi-trash"></i></button>
         </form>
     </div>
 </div>

internal/webui/templates/webmail_mfa_setup_required.html

@@ -17,7 +17,7 @@
     {{template "csrf_script" .}}
     <div class="toast-container position-fixed top-0 end-0 p-3" style="z-index: 1090;">
         {{range .flashes}}
-        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true" data-bs-autohide="false">
+        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true">
             <div class="d-flex">
                 <div class="toast-body">
                     <i class="bi bi-{{if eq .Category "error"}}exclamation-triangle{{else if eq .Category "success"}}check-circle{{else}}info-circle{{end}} me-2"></i>

internal/webui/templates/webmail_rules.html

@@ -23,6 +23,7 @@
                 <button type="button" onclick="openCompose('/webmail/mail/compose')" class="btn btn-outline-light btn-sm"><i class="bi bi-pencil-square me-1"></i>Compose</button>
                 <a href="/webmail/rules" class="btn btn-light btn-sm"><i class="bi bi-funnel me-1"></i>Rules</a>
                 <a href="/webmail/certs" class="btn btn-outline-light btn-sm"><i class="bi bi-shield-lock me-1"></i>Certs</a>
+                <a href="/webmail/signatures" class="btn btn-outline-light btn-sm"><i class="bi bi-pen me-1"></i>Signatures</a>
                 <a href="/webmail/account" class="btn btn-outline-light btn-sm"><i class="bi bi-gear me-1"></i>Account</a>
                 <form method="post" action="/webmail/logout" class="d-inline">
                     <button type="submit" class="btn btn-outline-light btn-sm"><i class="bi bi-box-arrow-right me-1"></i>Sign out</button>
@@ -33,7 +34,7 @@
 
     <div class="toast-container position-fixed top-0 end-0 p-3" style="z-index: 1090;">
         {{range .flashes}}
-        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true" data-bs-autohide="false">
+        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true">
             <div class="d-flex">
                 <div class="toast-body">
                     <i class="bi bi-{{if eq .Category "error"}}exclamation-triangle{{else if eq .Category "success"}}check-circle{{else}}info-circle{{end}} me-2"></i>
@@ -80,7 +81,7 @@
                             <label class="form-label">Then</label>
                             <select class="form-select" name="action" id="rule_action">
                                 <option value="move_to_folder">Move to folder</option>
-                                <option value="mark_as_spam">Mark as Spam</option>
+                                <option value="mark_as_spam">Mark as Junk</option>
                                 <option value="delete">Delete</option>
                                 <option value="mark_read">Mark as read</option>
                             </select>
@@ -136,7 +137,7 @@
                                 <td><code>{{ruleSummary .}}</code></td>
                                 <td>
                                     {{if eq .Action "move_to_folder"}}Move to <strong>{{.ActionValue}}</strong>
-                                    {{else if eq .Action "mark_as_spam"}}<span class="text-warning">Mark as Spam</span>
+                                    {{else if eq .Action "mark_as_spam"}}<span class="text-warning">Mark as Junk</span>
                                     {{else if eq .Action "delete"}}<span class="text-danger">Delete</span>
                                     {{else}}Mark as read{{end}}
                                 </td>

internal/webui/templates/webmail_signatures.html

@@ -0,0 +1,149 @@
+{{define "webmail_signatures.html"}}
+<!DOCTYPE html>
+<html lang="en" data-bs-theme="dark">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Signatures - Webmail</title>
+    <link href="/webmail/static/vendor/bootstrap/css/bootstrap.min.css" rel="stylesheet">
+    <link href="/webmail/static/vendor/bootstrap-icons/font/bootstrap-icons.css" rel="stylesheet">
+    <link href="/webmail/static/vendor/quill/quill.snow.css" rel="stylesheet">
+    <style>
+        body { background-color: #1a1a1a; color: #e0e0e0; }
+        .card { background-color: #2d2d2d; border: 1px solid #404040; }
+        .sig-preview { background-color: #fff; color: #000; border-radius: 6px; padding: .75rem; max-height: 140px; overflow: hidden; }
+        #sigEditor { height: 180px; background-color: #fff; color: #000; }
+        .ql-toolbar.ql-snow { background-color: #333; border-color: #404040; border-top-left-radius: .375rem; border-top-right-radius: .375rem; }
+        .ql-container.ql-snow { border-color: #404040; border-bottom-left-radius: .375rem; border-bottom-right-radius: .375rem; }
+        .ql-snow .ql-stroke { stroke: #c8c8c8; }
+        .ql-snow .ql-fill, .ql-snow .ql-stroke.ql-fill { fill: #c8c8c8; }
+        .ql-snow .ql-picker { color: #c8c8c8; }
+        .ql-snow .ql-picker-options { background-color: #2d2d2d; border-color: #404040; }
+        .ql-snow .ql-picker-item { color: #c8c8c8; }
+    </style>
+</head>
+<body>
+    {{template "csrf_script" .}}
+    <nav class="navbar navbar-expand-lg navbar-dark bg-dark mb-4">
+        <div class="container-fluid">
+            <span class="navbar-brand mb-0 h1"><i class="bi bi-inbox-fill me-2"></i>Webmail <small class="text-muted">{{.mailbox.Email}}</small></span>
+            <div class="navbar-nav flex-row gap-2 ms-auto">
+                <a href="/webmail/mail/INBOX" class="btn btn-outline-light btn-sm"><i class="bi bi-envelope me-1"></i>Mail</a>
+                <button type="button" onclick="openCompose('/webmail/mail/compose')" class="btn btn-outline-light btn-sm"><i class="bi bi-pencil-square me-1"></i>Compose</button>
+                <a href="/webmail/rules" class="btn btn-outline-light btn-sm"><i class="bi bi-funnel me-1"></i>Rules</a>
+                <a href="/webmail/certs" class="btn btn-outline-light btn-sm"><i class="bi bi-shield-lock me-1"></i>Certs</a>
+                <a href="/webmail/signatures" class="btn btn-light btn-sm"><i class="bi bi-pen me-1"></i>Signatures</a>
+                <a href="/webmail/account" class="btn btn-outline-light btn-sm"><i class="bi bi-gear me-1"></i>Account</a>
+                <form method="post" action="/webmail/logout" class="d-inline">
+                    <button type="submit" class="btn btn-outline-light btn-sm"><i class="bi bi-box-arrow-right me-1"></i>Sign out</button>
+                </form>
+            </div>
+        </div>
+    </nav>
+
+    <div class="toast-container position-fixed top-0 end-0 p-3" style="z-index: 1090;">
+        {{range .flashes}}
+        <div class="toast align-items-center text-bg-{{if eq .Category "error"}}danger{{else}}{{.Category}}{{end}} border-0" role="alert" aria-live="assertive" aria-atomic="true">
+            <div class="d-flex">
+                <div class="toast-body">
+                    <i class="bi bi-{{if eq .Category "error"}}exclamation-triangle{{else if eq .Category "success"}}check-circle{{else}}info-circle{{end}} me-2"></i>
+                    {{.Message}}
+                </div>
+                <button type="button" class="btn-close btn-close-white me-2 m-auto" data-bs-dismiss="toast" aria-label="Close"></button>
+            </div>
+        </div>
+        {{end}}
+    </div>
+
+    <div class="container pb-5">
+        <h2 class="mb-4"><i class="bi bi-pen me-2"></i>Signatures</h2>
+
+        <div class="row">
+            <div class="col-lg-6 mb-4">
+                <div class="card">
+                    <div class="card-header"><h5 class="mb-0">Your signatures</h5></div>
+                    <div class="card-body">
+                        {{if .signatures}}
+                        {{range .signatures}}
+                        <div class="border rounded p-2 mb-3" style="border-color: #404040 !important;">
+                            <div class="d-flex justify-content-between align-items-start mb-2">
+                                <div>
+                                    <strong>{{.Name}}</strong>
+                                    {{if .IsDefaultNew}}<span class="badge bg-primary ms-1">Default: New</span>{{end}}
+                                    {{if .IsDefaultReply}}<span class="badge bg-info text-dark ms-1">Default: Reply/Forward</span>{{end}}
+                                </div>
+                                <div class="btn-group btn-group-sm">
+                                    <a href="/webmail/signatures?edit={{.ID}}" class="btn btn-outline-secondary" title="Edit"><i class="bi bi-pencil"></i></a>
+                                    <form method="post" action="/webmail/signatures/{{.ID}}/delete" class="d-inline" onsubmit="return confirm('Delete signature &quot;{{.Name}}&quot;?');">
+                                        <button type="submit" class="btn btn-outline-danger" title="Delete"><i class="bi bi-trash"></i></button>
+                                    </form>
+                                </div>
+                            </div>
+                            <div class="sig-preview mb-2">{{.ContentHTML | safe}}</div>
+                            <div class="btn-group btn-group-sm">
+                                <form method="post" action="/webmail/signatures/{{if .IsDefaultNew}}0{{else}}{{.ID}}{{end}}/default?which=new" class="d-inline">
+                                    <button type="submit" class="btn {{if .IsDefaultNew}}btn-primary{{else}}btn-outline-secondary{{end}}">{{if .IsDefaultNew}}✓ Default for new{{else}}Use for new{{end}}</button>
+                                </form>
+                                <form method="post" action="/webmail/signatures/{{if .IsDefaultReply}}0{{else}}{{.ID}}{{end}}/default?which=reply" class="d-inline">
+                                    <button type="submit" class="btn {{if .IsDefaultReply}}btn-info text-dark{{else}}btn-outline-secondary{{end}}">{{if .IsDefaultReply}}✓ Default for reply/forward{{else}}Use for reply/forward{{end}}</button>
+                                </form>
+                            </div>
+                        </div>
+                        {{end}}
+                        {{else}}
+                        <p class="text-muted mb-0">No signatures yet — add one to have it available in compose.</p>
+                        {{end}}
+                    </div>
+                </div>
+            </div>
+
+            <div class="col-lg-6 mb-4">
+                <div class="card">
+                    <div class="card-header"><h5 class="mb-0">{{if .editing}}Edit signature{{else}}New signature{{end}}</h5></div>
+                    <div class="card-body">
+                        <form method="POST" action="/webmail/signatures/save" id="sigForm">
+                            <input type="hidden" name="id" value="{{if .editing}}{{.editing.ID}}{{end}}">
+                            <div class="mb-3">
+                                <label class="form-label">Name</label>
+                                <input type="text" class="form-control" name="name" value="{{if .editing}}{{.editing.Name}}{{end}}" placeholder="e.g. Work, Personal" required>
+                            </div>
+                            <div class="mb-3">
+                                <label class="form-label">Content</label>
+                                <div id="sigEditor"></div>
+                                <textarea name="content_html" style="display: none;"></textarea>
+                                <div id="sig_html_seed" style="display: none;">{{if .editing}}{{.editing.ContentHTML}}{{end}}</div>
+                                <div class="form-text">Plain text works fine too — just don't use the formatting toolbar. A blank signature is also valid (e.g. to temporarily disable one without deleting it).</div>
+                            </div>
+                            <button type="submit" class="btn btn-primary"><i class="bi bi-check-lg me-1"></i>Save</button>
+                            {{if .editing}}<a href="/webmail/signatures" class="btn btn-outline-secondary">Cancel</a>{{end}}
+                        </form>
+                    </div>
+                </div>
+            </div>
+        </div>
+    </div>
+
+    {{template "compose_widget" .}}
+
+    <script src="/webmail/static/vendor/bootstrap/js/bootstrap.bundle.min.js"></script>
+    <script src="/webmail/static/vendor/quill/quill.js"></script>
+    <script>
+        document.addEventListener('DOMContentLoaded', function() {
+            document.querySelectorAll('.toast').forEach(function(el) { new bootstrap.Toast(el, {delay: 5000}).show(); });
+        });
+
+        var sigQuill = new Quill('#sigEditor', {
+            theme: 'snow',
+            modules: { toolbar: [['bold', 'italic', 'underline'], [{ color: [] }], ['link', 'image'], ['clean']] },
+        });
+        (function() {
+            const seed = document.getElementById('sig_html_seed');
+            if (seed && seed.innerHTML.trim()) sigQuill.root.innerHTML = seed.innerHTML;
+        })();
+        document.getElementById('sigForm').addEventListener('submit', function() {
+            document.querySelector('[name="content_html"]').value = sigQuill.root.innerHTML;
+        });
+    </script>
+</body>
+</html>
+{{end}}

internal/webui/webmail_client_test.go

@@ -451,6 +451,93 @@ func TestWebmailComposeReplyPrefill(t *testing.T) {
 	}
 }
 
+// extractSeed pulls out #body_html_seed's own content from a rendered compose page —
+// the seed div can itself contain a nested <div> (a signature's wrapper), so its end
+// is located via the exact markup immediately following the seed div's closing tag in
+// webmail_compose.html, not just "the next </div>" (which would match the nested one).
+func extractSeed(t *testing.T, page string) string {
+	t.Helper()
+	const openMarker = `id="body_html_seed" style="display: none;">`
+	const closeMarker = "</div>\n    </form>"
+	start := strings.Index(page, openMarker)
+	if start < 0 {
+		t.Fatal("body_html_seed not found in rendered page")
+	}
+	start += len(openMarker)
+	end := strings.Index(page[start:], closeMarker)
+	if end < 0 {
+		t.Fatal("body_html_seed's closing markup not found in rendered page")
+	}
+	return page[start : start+end]
+}
+
+// TestWebmailComposeDefaultSignatureInsertion confirms a mailbox's default-for-new
+// signature is auto-inserted into a brand-new compose, and its (possibly different)
+// default-for-reply signature is auto-inserted into a reply — both above the quoted
+// original, matching where a real signature belongs.
+func TestWebmailComposeDefaultSignatureInsertion(t *testing.T) {
+	app := newTestApp(t)
+	mux := app.Mux()
+	domains, _ := app.DB.ListDomains()
+	mailboxID := createTestMailboxWithPassword(t, app, "sigcompose@example.com", domains[0].ID, "sigcompose-password-1!")
+	cookie := webmailLoginSession(t, app, mailboxID)
+
+	newSigID, err := app.DB.CreateSignature(mailboxID, "New", "<p>Sent from my desk</p>")
+	if err != nil {
+		t.Fatal(err)
+	}
+	replySigID, err := app.DB.CreateSignature(mailboxID, "Reply", "<p>Sent on the go</p>")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := app.DB.SetDefaultSignature(mailboxID, newSigID, false); err != nil {
+		t.Fatal(err)
+	}
+	if err := app.DB.SetDefaultSignature(mailboxID, replySigID, true); err != nil {
+		t.Fatal(err)
+	}
+
+	// Brand-new compose gets the "new" default.
+	req := httptest.NewRequest(http.MethodGet, MailboxPrefix+"/mail/compose", nil)
+	req.AddCookie(cookie)
+	rec := httptest.NewRecorder()
+	mux.ServeHTTP(rec, req)
+	body := rec.Body.String()
+	// The picker's hidden .sig-data divs legitimately contain every signature's HTML
+	// (so the JS can swap between them client-side) — only the seed div (what actually
+	// loads into the editor) should be checked for which one was auto-inserted. The
+	// seed div's own content can itself contain a nested <div> (the signature's
+	// wrapper), so its end is found via the exact markup that follows the seed div's
+	// closing tag in the template, not just "the next </div>".
+	seed := extractSeed(t, body)
+	if !strings.Contains(seed, "Sent from my desk") {
+		t.Errorf("expected the default-for-new signature inserted, got seed:\n%s", seed)
+	}
+	if strings.Contains(seed, "Sent on the go") {
+		t.Error("did not expect the reply signature in a brand-new compose's seed")
+	}
+
+	// Reply gets the "reply" default instead, above the quote.
+	raw := "From: original@example.com\r\nTo: sigcompose@example.com\r\nSubject: Hi\r\nMessage-Id: <o1@example.com>\r\n\r\noriginal body"
+	uid, err := app.Mailstore.StoreMessage(mailboxID, "INBOX", []byte(raw), "o1@example.com", "original@example.com", "Hi")
+	if err != nil {
+		t.Fatal(err)
+	}
+	replyReq := httptest.NewRequest(http.MethodGet, MailboxPrefix+"/mail/compose?reply="+strconv.FormatInt(uid, 10)+"&folder=INBOX", nil)
+	replyReq.AddCookie(cookie)
+	replyRec := httptest.NewRecorder()
+	mux.ServeHTTP(replyRec, replyReq)
+	replySeed := extractSeed(t, replyRec.Body.String())
+	if !strings.Contains(replySeed, "Sent on the go") {
+		t.Errorf("expected the default-for-reply signature inserted into the seed, got:\n%s", replySeed)
+	}
+	sigIdx := strings.Index(replySeed, "Sent on the go")
+	quoteIdx := strings.Index(replySeed, "wrote:")
+	if sigIdx < 0 || quoteIdx < 0 || sigIdx > quoteIdx {
+		t.Error("expected the signature above the quoted original")
+	}
+}
+
 // TestWebmailMoveAndDeleteMessage confirms moving a message changes its folder, and
 // deleting from a non-Trash folder moves to Trash first, requiring a second delete to
 // actually remove it.

internal/webui/webmail_compose.go

@@ -40,7 +40,28 @@ func (a *App) composeFormData(mbox *db.Mailbox) M {
 	}
 	identities, _ := a.DB.ListSMIMEIdentities(mbox.ID)
 	pgpContacts, _ := a.DB.ListPGPContacts(mbox.ID)
-	return M{"mailbox": mbox, "send_as_options": sendAsOptions, "smime_identities": identities, "pgp_contacts": pgpContacts}
+	signatures, _ := a.DB.ListSignatures(mbox.ID)
+	return M{
+		"mailbox": mbox, "send_as_options": sendAsOptions, "smime_identities": identities, "pgp_contacts": pgpContacts,
+		"signatures": signatures,
+		// Always present (never a missing map key) so the template's {{eq
+		// $.default_signature_id .ID}} comparison never has to handle a nil operand —
+		// 0 is a safe "no default" sentinel since real ids start at 1 (AUTOINCREMENT).
+		"default_signature_id": int64(0),
+	}
+}
+
+// signatureMarkerID wraps every auto-inserted (or picker-inserted) signature's HTML in
+// a stable-id div — the compose page's JS looks for this element to swap the
+// signature in place when the user picks a different one, instead of needing to
+// somehow diff/guess which part of their freely-edited body is "the signature".
+const signatureMarkerID = "mailSignatureBlock"
+
+func wrapSignatureHTML(contentHTML string) string {
+	if strings.TrimSpace(contentHTML) == "" {
+		return ""
+	}
+	return `<div id="` + signatureMarkerID + `">` + contentHTML + `</div>`
 }
 
 // webmailComposeForm shows the compose page, optionally prefilled for a reply,
@@ -99,6 +120,27 @@ func (a *App) webmailComposeForm(w http.ResponseWriter, r *http.Request) {
 		}
 	}
 
+	// Signature auto-insertion: reply/forward gets the reply/forward default, a
+	// brand-new compose (mode == "") gets the new-message default. A reloaded draft
+	// is left exactly as saved — it may already contain whatever signature was there
+	// when it was saved, or none, and re-adding one here would duplicate it.
+	if mode != "draft" {
+		forReply := mode == "reply" || mode == "replyall" || mode == "forward"
+		if sig, err := a.DB.GetDefaultSignature(mbox.ID, forReply); err == nil && sig != nil {
+			data["default_signature_id"] = sig.ID
+			if wrapped := wrapSignatureHTML(sig.ContentHTML); wrapped != "" {
+				existing, _ := data["body_html"].(template.HTML)
+				body := string(existing)
+				if strings.HasPrefix(body, composeCursorHome) {
+					body = composeCursorHome + wrapped + strings.TrimPrefix(body, composeCursorHome)
+				} else {
+					body = composeCursorHome + wrapped + body
+				}
+				data["body_html"] = template.HTML(body)
+			}
+		}
+	}
+
 	a.render(w, r, "webmail_compose.html", data)
 }
 

internal/webui/webmail_folders_test.go

@@ -75,10 +75,12 @@ func TestWebmailFolderCreateRejectsStandardAndDuplicateNames(t *testing.T) {
 	}
 }
 
-// TestWebmailFolderDeleteMovesMessagesToInboxAndCannotDeleteStandard confirms
-// deleting a custom folder relocates its messages to INBOX, and that a standard
-// folder can't be deleted via the same route even if requested directly.
-func TestWebmailFolderDeleteMovesMessagesToInboxAndCannotDeleteStandard(t *testing.T) {
+// TestWebmailFolderDeleteMovesToTrashAndCannotDeleteStandard confirms deleting a
+// custom folder re-parents it (and its messages, untouched under the same flat name)
+// under Trash rather than relocating messages to INBOX — the folder itself becomes a
+// subfolder of Trash, not gone — and that a standard folder can't be deleted via the
+// same route even if requested directly.
+func TestWebmailFolderDeleteMovesToTrashAndCannotDeleteStandard(t *testing.T) {
 	app := newTestApp(t)
 	mux := app.Mux()
 	domains, _ := app.DB.ListDomains()
@@ -101,13 +103,19 @@ func TestWebmailFolderDeleteMovesMessagesToInboxAndCannotDeleteStandard(t *testi
 		t.Fatalf("delete folder: status=%d", rec.Code)
 	}
 
-	remaining, err := app.DB.ListMailboxFolders(mailboxID)
-	if err != nil || len(remaining) != 0 {
-		t.Fatalf("expected the folder record gone, got %v (err=%v)", remaining, err)
+	root, err := app.DB.FolderRoot(mailboxID, "Newsletters")
+	if err != nil || root != "Trash" {
+		t.Fatalf("expected Newsletters to now resolve under Trash, got root=%q (err=%v)", root, err)
+	}
+	// The message stays tagged with its own flat folder name, not moved to "Trash" —
+	// that's what makes it show up nested under Trash instead of dumped at its root.
+	msgs, err := app.DB.ListMessagesInFolder(mailboxID, "Newsletters")
+	if err != nil || len(msgs) != 1 {
+		t.Fatalf("expected the message to stay in Newsletters, got %d (err=%v)", len(msgs), err)
 	}
 	inboxMsgs, err := app.DB.ListMessagesInFolder(mailboxID, "INBOX")
-	if err != nil || len(inboxMsgs) != 1 {
-		t.Fatalf("expected the message relocated to INBOX, got %d (err=%v)", len(inboxMsgs), err)
+	if err != nil || len(inboxMsgs) != 0 {
+		t.Fatalf("expected nothing relocated to INBOX, got %d (err=%v)", len(inboxMsgs), err)
 	}
 
 	// Attempting to delete a standard folder must be rejected, not silently succeed.

internal/webui/webmail_mail.go

@@ -36,32 +36,11 @@ var htmlBodyPolicy = func() *bluemonday.Policy {
 // quote a plain-text-only original message's body when replying/forwarding.
 var plainTextPolicy = bluemonday.StrictPolicy()
 
-// standardMailFolders are always shown in the folder sidebar even when empty — the
-// rest of a mailbox's folder list is whatever filter-rule move_to_folder actions (or,
-// later, explicit folder creation) have actually produced messages in.
-var standardMailFolders = []string{"INBOX", "Spam", "Sent", "Drafts", "Trash"}
-
-func mergeFolders(custom []string) []string {
-	seen := make(map[string]bool, len(standardMailFolders)+len(custom))
-	out := make([]string, 0, len(standardMailFolders)+len(custom))
-	for _, f := range standardMailFolders {
-		seen[f] = true
-		out = append(out, f)
-	}
-	for _, f := range custom {
-		if !seen[f] {
-			seen[f] = true
-			out = append(out, f)
-		}
-	}
-	return out
-}
-
 // isStandardFolder reports whether name is one of the built-in folders every mailbox
 // always has — these can never be created, renamed, or deleted through the folder
-// management UI.
+// management UI, and never move (see db.StandardMailboxFolders).
 func isStandardFolder(name string) bool {
-	for _, f := range standardMailFolders {
+	for _, f := range db.StandardMailboxFolders {
 		if f == name {
 			return true
 		}
@@ -69,20 +48,69 @@ func isStandardFolder(name string) bool {
 	return false
 }
 
-// allFoldersFor is the full folder list for a mailbox: standard folders, plus every
-// folder that either holds at least one message (DistinctFoldersForMailbox) or was
-// explicitly created and is still empty (ListMailboxFolders) — a folder can exist via
-// either path, sometimes both.
+// allFoldersFor is the full folder list for a mailbox — see db.AllFoldersForMailbox.
 func (a *App) allFoldersFor(mailboxID int64) ([]string, error) {
-	fromMessages, err := a.DB.DistinctFoldersForMailbox(mailboxID)
-	if err != nil {
-		return nil, err
+	return a.DB.AllFoldersForMailbox(mailboxID)
+}
+
+// folderIcon picks a sidebar icon (a Bootstrap Icons class) that matches what each
+// standard folder actually is, instead of the same generic folder glyph for all of
+// them — INBOX and every custom folder keep the generic one.
+func folderIcon(name string) string {
+	switch name {
+	case "Trash":
+		return "bi-trash3"
+	case "Sent":
+		return "bi-send"
+	case "Drafts":
+		return "bi-journal-text"
+	case "Junk":
+		return "bi-shield-exclamation"
+	case "INBOX":
+		return "bi-inbox"
+	default:
+		return "bi-folder2"
 	}
-	explicit, err := a.DB.ListMailboxFolders(mailboxID)
-	if err != nil {
-		return nil, err
+}
+
+// folderViewNode is a fully-resolved sidebar tree node — everything
+// webmail_folder.html's recursive "folderTreeNode" template needs for one folder,
+// computed once here rather than threaded (unread/counts/active-folder) through every
+// level of the recursive {{template}} call, which only ever gets to pass a single `.`
+// value down.
+type folderViewNode struct {
+	Name       string
+	Icon       string
+	Total      int
+	Unread     int
+	Active     bool
+	Renameable bool // also gates showing the remove button and drag-and-drop reordering
+	CanAddKid  bool
+	IsSpam     bool // gates the "Clean up Junk" context-menu item
+	IsTrash    bool // gates the "Empty Trash" context-menu item
+	UnderTrash bool // gates "Delete permanently" / "Restore" for a folder already in Trash
+	Children   []*folderViewNode
+}
+
+// buildFolderView resolves db.FolderTree's nodes into folderViewNodes for one render.
+func buildFolderView(nodes []*db.FolderNode, active string, unread, counts map[string]int) []*folderViewNode {
+	var build func(n *db.FolderNode) *folderViewNode
+	build = func(n *db.FolderNode) *folderViewNode {
+		v := &folderViewNode{
+			Name: n.Name, Icon: folderIcon(n.Name), Total: counts[n.Name], Unread: unread[n.Name],
+			Active: n.Name == active, Renameable: n.Renameable, CanAddKid: n.CanAddKid,
+			IsSpam: n.Name == "Junk", IsTrash: n.Name == "Trash", UnderTrash: n.UnderTrash,
 		}
-	return mergeFolders(append(fromMessages, explicit...)), nil
+		for _, c := range n.Children {
+			v.Children = append(v.Children, build(c))
+		}
+		return v
+	}
+	out := make([]*folderViewNode, 0, len(nodes))
+	for _, n := range nodes {
+		out = append(out, build(n))
+	}
+	return out
 }
 
 // folderRow adds template-ready fields to a listed message so webmail_folder.html
@@ -90,6 +118,7 @@ func (a *App) allFoldersFor(mailboxID int64) ([]string, error) {
 type folderRow struct {
 	db.MailboxMessage
 	Unread  bool
+	Starred bool
 	// GroupExtra is set on the newest row of a same-subject run: how many older
 	// messages are collapsed under it (0 = not part of a group). Collapsed is set on
 	// each of those older rows, which the template hides until the group's expand
@@ -100,9 +129,9 @@ type folderRow struct {
 
 // sortLink builds the href for a clickable "From"/"Date" column header: clicking an
 // inactive column sorts by it descending; clicking the already-active column flips
-// direction; unreadOnly (and folder/query, via the caller building this against the
-// current URL) carries over so toggling sort never drops the unread filter.
-func sortLink(col string, unreadOnly bool, activeSortBy, activeSortDir string) string {
+// direction; unreadOnly/starredOnly (and folder/query, via the caller building this
+// against the current URL) carry over so toggling sort never drops another filter.
+func sortLink(col string, unreadOnly, starredOnly bool, activeSortBy, activeSortDir string) string {
 	v := url.Values{}
 	dir := "desc"
 	if activeSortBy == col {
@@ -121,6 +150,9 @@ func sortLink(col string, unreadOnly bool, activeSortBy, activeSortDir string) s
 	if unreadOnly {
 		v.Set("unread", "1")
 	}
+	if starredOnly {
+		v.Set("starred", "1")
+	}
 	if encoded := v.Encode(); encoded != "" {
 		return "?" + encoded
 	}
@@ -136,6 +168,18 @@ func isUnread(flags string) bool {
 	return true
 }
 
+// isStarred reports whether flags includes \Flagged — IMAP's standard "important/
+// starred" flag, reused as-is (see db.ToggleMessageStarred) rather than a new schema
+// column, so a desktop IMAP client's own star button and webmail's stay in sync.
+func isStarred(flags string) bool {
+	for _, f := range strings.Fields(flags) {
+		if f == `\Flagged` {
+			return true
+		}
+	}
+	return false
+}
+
 // normalizeSubjectForGrouping strips Re:/Fwd:/Fw: prefixes and case for comparison.
 // This is subject-based grouping, not References/In-Reply-To thread reconstruction
 // — a reply with a hand-edited subject line won't group with its original, and two
@@ -205,6 +249,10 @@ func (a *App) renderFolderOrSearch(w http.ResponseWriter, r *http.Request, folde
 	if err != nil {
 		a.Logger.Error("list folders for mailbox %d: %v", mbox.ID, err)
 	}
+	folderTreeRaw, err := a.DB.FolderTree(mbox.ID)
+	if err != nil {
+		a.Logger.Error("build folder tree for mailbox %d: %v", mbox.ID, err)
+	}
 	unreadCounts, err := a.DB.CountUnreadByFolder(mbox.ID)
 	if err != nil {
 		a.Logger.Error("count unread for mailbox %d: %v", mbox.ID, err)
@@ -213,6 +261,7 @@ func (a *App) renderFolderOrSearch(w http.ResponseWriter, r *http.Request, folde
 	if err != nil {
 		a.Logger.Error("count messages by folder for mailbox %d: %v", mbox.ID, err)
 	}
+	folderTree := buildFolderView(folderTreeRaw, folder, unreadCounts, folderCounts)
 
 	page := atoi(r.URL.Query().Get("page"))
 	if page < 1 {
@@ -220,6 +269,10 @@ func (a *App) renderFolderOrSearch(w http.ResponseWriter, r *http.Request, folde
 	}
 	offset := (page - 1) * webmailPageSize
 	unreadOnly := r.URL.Query().Get("unread") == "1"
+	// Starred filtering, like sort/grouping, only applies to a plain single-folder
+	// view — SearchMessagesInFolder has no starred param (a search result can span
+	// folders and is a much rarer thing to also want starred-filtered).
+	starredOnly := query == "" && r.URL.Query().Get("starred") == "1"
 	sortBy := r.URL.Query().Get("sort") // "" (id/date, default) or "from"
 	sortDir := r.URL.Query().Get("dir") // "" (desc, default) or "asc"
 
@@ -232,18 +285,18 @@ func (a *App) renderFolderOrSearch(w http.ResponseWriter, r *http.Request, folde
 		}
 		rows, err = a.DB.SearchMessagesInFolder(mbox.ID, folder, query, offset, webmailPageSize)
 	} else {
-		total, err = a.DB.CountMessagesInFolder(mbox.ID, folder, unreadOnly)
+		total, err = a.DB.CountMessagesInFolder(mbox.ID, folder, unreadOnly, starredOnly)
 		if err != nil {
 			a.Logger.Error("count messages in %s for mailbox %d: %v", folder, mbox.ID, err)
 		}
-		rows, err = a.DB.ListMessagesInFolderPage(mbox.ID, folder, unreadOnly, sortBy, sortDir, offset, webmailPageSize)
+		rows, err = a.DB.ListMessagesInFolderPage(mbox.ID, folder, unreadOnly, starredOnly, sortBy, sortDir, offset, webmailPageSize)
 	}
 	if err != nil {
 		setFlash(w, "error", "Error loading messages")
 	}
 	messages := make([]folderRow, 0, len(rows))
 	for _, m := range rows {
-		messages = append(messages, folderRow{MailboxMessage: m, Unread: isUnread(m.Flags)})
+		messages = append(messages, folderRow{MailboxMessage: m, Unread: isUnread(m.Flags), Starred: isStarred(m.Flags)})
 	}
 	// Grouping a cross-folder search's results by subject would mix messages that
 	// happen to share a subject across unrelated folders — only group a real,
@@ -257,6 +310,9 @@ func (a *App) renderFolderOrSearch(w http.ResponseWriter, r *http.Request, folde
 	if !unreadOnly {
 		unreadToggleV.Set("unread", "1")
 	}
+	if starredOnly {
+		unreadToggleV.Set("starred", "1")
+	}
 	if sortBy != "" {
 		unreadToggleV.Set("sort", sortBy)
 	}
@@ -265,12 +321,30 @@ func (a *App) renderFolderOrSearch(w http.ResponseWriter, r *http.Request, folde
 	}
 	unreadOnlyHref := "?" + unreadToggleV.Encode()
 
+	starredToggleV := url.Values{}
+	if !starredOnly {
+		starredToggleV.Set("starred", "1")
+	}
+	if unreadOnly {
+		starredToggleV.Set("unread", "1")
+	}
+	if sortBy != "" {
+		starredToggleV.Set("sort", sortBy)
+	}
+	if sortDir != "" {
+		starredToggleV.Set("dir", sortDir)
+	}
+	starredOnlyHref := "?" + starredToggleV.Encode()
+
 	pageHref := func(n int) string {
 		v := url.Values{}
 		v.Set("page", strconv.Itoa(n))
 		if unreadOnly {
 			v.Set("unread", "1")
 		}
+		if starredOnly {
+			v.Set("starred", "1")
+		}
 		if sortBy != "" {
 			v.Set("sort", sortBy)
 		}
@@ -281,14 +355,15 @@ func (a *App) renderFolderOrSearch(w http.ResponseWriter, r *http.Request, folde
 	}
 
 	a.render(w, r, "webmail_folder.html", M{
-		"mailbox": mbox, "folders": folders, "active_folder": folder,
+		"mailbox": mbox, "folders": folders, "folder_tree": folderTree, "active_folder": folder,
 		"messages": messages, "page": page, "total": total,
 		"has_next": offset+len(rows) < total, "has_prev": page > 1,
 		"search_query": query, "unread_counts": unreadCounts, "folder_counts": folderCounts,
-		"unread_only": unreadOnly, "sort_by": sortBy, "sort_dir": sortDir,
-		"sort_from_href":   sortLink("from", unreadOnly, sortBy, sortDir),
-		"sort_date_href":   sortLink("", unreadOnly, sortBy, sortDir),
+		"unread_only": unreadOnly, "starred_only": starredOnly, "sort_by": sortBy, "sort_dir": sortDir,
+		"sort_from_href":   sortLink("from", unreadOnly, starredOnly, sortBy, sortDir),
+		"sort_date_href":   sortLink("", unreadOnly, starredOnly, sortBy, sortDir),
 		"unread_only_href": unreadOnlyHref,
+		"starred_only_href": starredOnlyHref,
 		"prev_href":        pageHref(page - 1),
 		"next_href":        pageHref(page + 1),
 		"flashes":          popFlashes(w, r),
@@ -334,9 +409,18 @@ func (a *App) loadMessageForView(w http.ResponseWriter, r *http.Request, mbox *d
 	if parsed.HTMLBody != "" {
 		htmlBody = template.HTML(htmlBodyPolicy.Sanitize(parsed.HTMLBody))
 	}
+	// Whether this message is already somewhere under Trash (literally "Trash", or a
+	// folder that was itself deleted into Trash) — the delete button's wording/action
+	// and whether a Restore button appears both depend on this, not just a literal
+	// `folder == "Trash"` check (see webmailMessageDelete for the same distinction on
+	// the backend side).
+	underTrash := false
+	if root, err := a.DB.FolderRoot(mbox.ID, folder); err == nil {
+		underTrash = root == "Trash"
+	}
 
 	return M{
-		"mailbox": mbox, "folders": folders, "active_folder": folder,
+		"mailbox": mbox, "folders": folders, "active_folder": folder, "under_trash": underTrash,
 		"uid": uid, "parsed": parsed, "html_body": htmlBody, "smime": smimeStatus, "pgp": pgpStatus,
 		"message_url": MailboxPrefix + "/mail/" + folder + "/" + strconv.FormatInt(uid, 10),
 	}, true
@@ -398,8 +482,10 @@ func (a *App) messageAccessible(mailboxID int64, folder string, uid int64) (*db.
 	return msg, true
 }
 
-// webmailMessageDelete moves a message to Trash — or, if it's already in Trash,
-// permanently deletes it (ciphertext, index row, and frees the quota).
+// webmailMessageDelete moves a message to Trash — or, if it's already somewhere under
+// Trash (literally "Trash", or a folder that was itself deleted into Trash — see
+// webmailDeleteFolder), permanently deletes it (ciphertext, index row, and frees the
+// quota).
 func (a *App) webmailMessageDelete(w http.ResponseWriter, r *http.Request) {
 	mbox := mailboxFromContext(r)
 	folder := r.PathValue("folder")
@@ -408,7 +494,7 @@ func (a *App) webmailMessageDelete(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if folder == "Trash" {
+	if root, err := a.DB.FolderRoot(mbox.ID, folder); err == nil && root == "Trash" {
 		if err := a.Mailstore.DeleteMessage(mbox.ID, uid); err != nil {
 			setFlash(w, "error", "Error deleting message")
 		} else {
@@ -417,7 +503,7 @@ func (a *App) webmailMessageDelete(w http.ResponseWriter, r *http.Request) {
 		http.Redirect(w, r, MailboxPrefix+"/mail/Trash", http.StatusFound)
 		return
 	}
-	if err := a.DB.MoveMessage(mbox.ID, uid, "Trash"); err != nil {
+	if err := a.DB.MoveMessageToTrash(mbox.ID, uid); err != nil {
 		setFlash(w, "error", "Error moving message to Trash")
 	} else {
 		setFlash(w, "success", "Message moved to Trash")
@@ -425,6 +511,29 @@ func (a *App) webmailMessageDelete(w http.ResponseWriter, r *http.Request) {
 	http.Redirect(w, r, MailboxPrefix+"/mail/"+folder, http.StatusFound)
 }
 
+// webmailRestoreMessage moves a message back to the folder it was in before it was
+// trashed (or INBOX if that's unknown — see db.RestoreMessage). Only a message
+// currently somewhere under Trash can be restored this way.
+func (a *App) webmailRestoreMessage(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	folder := r.PathValue("folder")
+	uid := int64(atoi(r.PathValue("uid")))
+	if _, ok := a.webmailMessageWithAccess(w, r, mbox.ID, folder, uid); !ok {
+		return
+	}
+	if root, err := a.DB.FolderRoot(mbox.ID, folder); err != nil || root != "Trash" {
+		setFlash(w, "error", "Only a message in Trash can be restored")
+		http.Redirect(w, r, MailboxPrefix+"/mail/"+folder, http.StatusFound)
+		return
+	}
+	if err := a.DB.RestoreMessage(mbox.ID, uid); err != nil {
+		setFlash(w, "error", "Error restoring message")
+	} else {
+		setFlash(w, "success", "Message restored")
+	}
+	http.Redirect(w, r, MailboxPrefix+"/mail/Trash", http.StatusFound)
+}
+
 // webmailMessageMove reassigns a message to a different (existing or freshly named)
 // folder, e.g. from the message view's "Move to..." control.
 func (a *App) webmailMessageMove(w http.ResponseWriter, r *http.Request) {
@@ -487,11 +596,13 @@ func (a *App) webmailBulkAction(w http.ResponseWriter, r *http.Request) {
 		var err error
 		switch action {
 		case "delete":
-			if folder == "Trash" {
+			if root, rootErr := a.DB.FolderRoot(mbox.ID, folder); rootErr == nil && root == "Trash" {
 				err = a.Mailstore.DeleteMessage(mbox.ID, uid)
 			} else {
-				err = a.DB.MoveMessage(mbox.ID, uid, "Trash")
+				err = a.DB.MoveMessageToTrash(mbox.ID, uid)
 			}
+		case "restore":
+			err = a.DB.RestoreMessage(mbox.ID, uid)
 		case "move":
 			err = a.DB.MoveMessage(mbox.ID, uid, target)
 		case "read":
@@ -546,12 +657,21 @@ func (a *App) webmailAttachmentDownload(w http.ResponseWriter, r *http.Request)
 
 const maxFolderNameLen = 60
 
-// webmailAddFolder creates a new custom folder from the sidebar's "+ New folder"
-// form. A standard folder name, an empty name, or a name that already exists is
-// rejected with a flash rather than silently accepted/ignored.
+// webmailAddFolder creates a new custom folder as a child of the folder the sidebar's
+// context menu was opened on (see webmail_folder.html's "New folder" — always the
+// right-clicked node, INBOX or an existing custom folder still under it; the request
+// itself is re-validated here, never trusted just because the menu item was hidden
+// client-side elsewhere). A standard folder name, an empty name, a name containing
+// "/", or a name that already exists anywhere in the mailbox (folder names are unique
+// per mailbox regardless of nesting — messages reference a folder by that name alone)
+// is rejected with a flash rather than silently accepted/ignored.
 func (a *App) webmailAddFolder(w http.ResponseWriter, r *http.Request) {
 	mbox := mailboxFromContext(r)
 	name := strings.TrimSpace(r.FormValue("name"))
+	parent := strings.TrimSpace(r.FormValue("parent"))
+	if parent == "" {
+		parent = "INBOX"
+	}
 
 	fail := func(msg string) {
 		setFlash(w, "error", msg)
@@ -564,6 +684,9 @@ func (a *App) webmailAddFolder(w http.ResponseWriter, r *http.Request) {
 	case len(name) > maxFolderNameLen:
 		fail("Folder name is too long")
 		return
+	case strings.Contains(name, "/"):
+		fail("Folder name can't contain \"/\"")
+		return
 	case isStandardFolder(name):
 		fail(name + " already exists")
 		return
@@ -573,13 +696,26 @@ func (a *App) webmailAddFolder(w http.ResponseWriter, r *http.Request) {
 		fail("Error creating folder")
 		return
 	}
+	found := false
 	for _, f := range existing {
 		if strings.EqualFold(f, name) {
 			fail("A folder named " + f + " already exists")
 			return
 		}
+		if strings.EqualFold(f, parent) {
+			parent = f
+			found = true
 		}
-	if err := a.DB.CreateMailboxFolder(mbox.ID, name); err != nil {
+	}
+	if !found {
+		fail("Folder no longer exists")
+		return
+	}
+	if root, err := a.DB.FolderRoot(mbox.ID, parent); err != nil || root != "INBOX" {
+		fail("New folders can only go under Inbox")
+		return
+	}
+	if err := a.DB.CreateMailboxFolderUnder(mbox.ID, name, parent); err != nil {
 		fail("Error creating folder")
 		return
 	}
@@ -587,10 +723,14 @@ func (a *App) webmailAddFolder(w http.ResponseWriter, r *http.Request) {
 	http.Redirect(w, r, MailboxPrefix+"/mail/"+name, http.StatusFound)
 }
 
-// webmailDeleteFolder removes a custom folder, moving any messages still in it to
-// INBOX first — a folder is never left holding mail nothing can browse to anymore.
-// Standard folders (checked server-side, not just hidden client-side) can't be
-// removed this way.
+// webmailDeleteFolder "deletes" a custom folder by re-parenting it (and, since its
+// descendants reference it by row id rather than a materialized path, its whole
+// subtree along with it) under Trash — its messages are never touched or relocated,
+// they're still tagged with the same flat folder name(s) they always were, which now
+// simply render nested under Trash instead of under Inbox. This is the only way a
+// folder ever moves under Trash, precisely so Trash mirrors whatever structure was
+// deleted from, instead of dumping everything into one flat pile. Standard folders
+// (checked server-side, not just hidden client-side) can't be removed this way.
 func (a *App) webmailDeleteFolder(w http.ResponseWriter, r *http.Request) {
 	mbox := mailboxFromContext(r)
 	name := r.PathValue("name")
@@ -600,15 +740,258 @@ func (a *App) webmailDeleteFolder(w http.ResponseWriter, r *http.Request) {
 		http.Redirect(w, r, MailboxPrefix+"/mail/INBOX", http.StatusFound)
 		return
 	}
-	if err := a.DB.MoveAllMessagesInFolder(mbox.ID, name, "INBOX"); err != nil {
-		setFlash(w, "error", "Error removing folder")
-		http.Redirect(w, r, MailboxPrefix+"/mail/INBOX", http.StatusFound)
-		return
-	}
-	if err := a.DB.DeleteMailboxFolder(mbox.ID, name); err != nil {
-		setFlash(w, "error", "Error removing folder")
+	if err := a.DB.MoveFolderToTrash(mbox.ID, name); err != nil {
+		setFlash(w, "error", "Error deleting folder")
 	} else {
-		setFlash(w, "success", "Folder "+name+" removed — any mail in it moved to INBOX")
+		setFlash(w, "success", "Folder "+name+" moved to Trash")
 	}
 	http.Redirect(w, r, MailboxPrefix+"/mail/INBOX", http.StatusFound)
 }
+
+// webmailRenameFolder renames a folder from the sidebar's right-click context menu —
+// only a custom folder still under INBOX (not INBOX itself, not Junk/Sent/Drafts, and
+// not a folder that's been deleted into Trash — that subtree is a historical record,
+// not something to keep editing). A single-row name change is enough: children
+// reference their parent by row id, not by name, so they stay correctly nested
+// without any further writes (see db.RenameMailboxFolder).
+func (a *App) webmailRenameFolder(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	oldName := r.PathValue("name")
+	newName := strings.TrimSpace(r.FormValue("new_name"))
+
+	fail := func(msg string) {
+		setFlash(w, "error", msg)
+		http.Redirect(w, r, MailboxPrefix+"/mail/"+oldName, http.StatusFound)
+	}
+	if root, err := a.DB.FolderRoot(mbox.ID, oldName); err != nil || isStandardFolder(oldName) || root != "INBOX" {
+		fail(oldName + " can't be renamed")
+		return
+	}
+	switch {
+	case newName == "":
+		fail("Folder name is required")
+		return
+	case len(newName) > maxFolderNameLen:
+		fail("Folder name is too long")
+		return
+	case strings.Contains(newName, "/"):
+		fail("Folder name can't contain \"/\"")
+		return
+	case isStandardFolder(newName):
+		fail(newName + " already exists")
+		return
+	}
+	existing, err := a.allFoldersFor(mbox.ID)
+	if err != nil {
+		fail("Error renaming folder")
+		return
+	}
+	for _, f := range existing {
+		if strings.EqualFold(f, newName) && !strings.EqualFold(f, oldName) {
+			fail("A folder named " + f + " already exists")
+			return
+		}
+	}
+	if err := a.DB.RenameMailboxFolder(mbox.ID, oldName, newName); err != nil {
+		fail("Error renaming folder")
+		return
+	}
+	setFlash(w, "success", "Folder renamed to "+newName)
+	http.Redirect(w, r, MailboxPrefix+"/mail/"+newName, http.StatusFound)
+}
+
+// webmailMarkAllRead marks every unread message in one folder as read — the sidebar
+// context menu's "Mark all as read", available on every folder including INBOX.
+func (a *App) webmailMarkAllRead(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	folder := r.PathValue("folder")
+	if err := a.DB.MarkAllReadInFolder(mbox.ID, folder); err != nil {
+		setFlash(w, "error", "Error marking messages as read")
+	} else {
+		setFlash(w, "success", "All messages in "+folder+" marked as read")
+	}
+	http.Redirect(w, r, MailboxPrefix+"/mail/"+folder, http.StatusFound)
+}
+
+// deleteFolderSubtreePermanently permanently deletes every message across start and
+// every folder nested under it — ciphertext, index row, and freed quota, via the same
+// per-message Mailstore.DeleteMessage path webmailMessageDelete already uses for a
+// single already-in-Trash message — and removes the esrv_mailbox_folders records for
+// whatever's now empty, so a permanently-deleted folder doesn't linger as an empty
+// shell the way a merely-emptied one does. removeStartRecord controls whether start's
+// OWN record is removed too: false for the 5 standard folders (Empty Trash/Clean up
+// Junk — they always exist, nothing to remove even if a stray row happens to), true
+// for a genuine custom folder someone is permanently deleting from within Trash.
+func (a *App) deleteFolderSubtreePermanently(mbox *db.Mailbox, start string, removeStartRecord bool) (int, error) {
+	names, err := a.DB.FolderSubtreeNames(mbox.ID, start)
+	if err != nil {
+		return 0, err
+	}
+	n := 0
+	for _, name := range names {
+		rows, err := a.DB.ListMessagesInFolder(mbox.ID, name)
+		if err != nil {
+			a.Logger.Error("list messages in %s for mailbox %d: %v", name, mbox.ID, err)
+			continue
+		}
+		for _, m := range rows {
+			if err := a.Mailstore.DeleteMessage(mbox.ID, m.ID); err != nil {
+				a.Logger.Error("permanently delete message %d for mailbox %d: %v", m.ID, mbox.ID, err)
+				continue
+			}
+			n++
+		}
+	}
+	toRemove := make([]string, 0, len(names))
+	for _, name := range names {
+		if name == start && !removeStartRecord {
+			continue
+		}
+		toRemove = append(toRemove, name)
+	}
+	if err := a.DB.DeleteFolderRows(mbox.ID, toRemove); err != nil {
+		a.Logger.Error("remove folder records for mailbox %d: %v", mbox.ID, err)
+	}
+	return n, nil
+}
+
+// webmailEmptyTrash permanently deletes every message in Trash and anything deleted
+// into it, and removes those now-empty folder records too (see
+// deleteFolderSubtreePermanently) — Trash-only, enforced server-side (the sidebar
+// only ever shows this action on Trash, but the route itself doesn't trust that).
+func (a *App) webmailEmptyTrash(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	folder := r.PathValue("folder")
+	if folder != "Trash" {
+		setFlash(w, "error", "Only Trash can be emptied")
+		http.Redirect(w, r, MailboxPrefix+"/mail/"+folder, http.StatusFound)
+		return
+	}
+	n, err := a.deleteFolderSubtreePermanently(mbox, "Trash", false)
+	if err != nil {
+		setFlash(w, "error", "Error emptying Trash")
+		http.Redirect(w, r, MailboxPrefix+"/mail/Trash", http.StatusFound)
+		return
+	}
+	setFlash(w, "success", fmt.Sprintf("Trash emptied (%d message(s) permanently deleted)", n))
+	http.Redirect(w, r, MailboxPrefix+"/mail/Trash", http.StatusFound)
+}
+
+// webmailCleanSpam permanently deletes every message in Junk — no move to Trash, no
+// recovery (see deleteFolderSubtreePermanently). Junk-only, enforced server-side.
+func (a *App) webmailCleanSpam(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	folder := r.PathValue("folder")
+	if folder != "Junk" {
+		setFlash(w, "error", "Only Junk can be cleaned up")
+		http.Redirect(w, r, MailboxPrefix+"/mail/"+folder, http.StatusFound)
+		return
+	}
+	n, err := a.deleteFolderSubtreePermanently(mbox, "Junk", false)
+	if err != nil {
+		setFlash(w, "error", "Error cleaning up Junk")
+		http.Redirect(w, r, MailboxPrefix+"/mail/Junk", http.StatusFound)
+		return
+	}
+	setFlash(w, "success", fmt.Sprintf("Junk cleaned up (%d message(s) permanently deleted)", n))
+	http.Redirect(w, r, MailboxPrefix+"/mail/Junk", http.StatusFound)
+}
+
+// webmailDeleteFolderPermanently permanently removes one specific folder that's
+// already been deleted into Trash (and whatever's nested under it) — messages and
+// all, no further move, no recovery. Only a folder currently under Trash can be
+// removed this way (checked server-side); a folder still under INBOX goes through
+// webmailDeleteFolder (move to Trash) instead — permanently deleting an active folder
+// isn't offered directly, only after it's already been trashed once.
+func (a *App) webmailDeleteFolderPermanently(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	name := r.PathValue("name")
+
+	if isStandardFolder(name) {
+		setFlash(w, "error", name+" can't be removed")
+		http.Redirect(w, r, MailboxPrefix+"/mail/Trash", http.StatusFound)
+		return
+	}
+	if root, err := a.DB.FolderRoot(mbox.ID, name); err != nil || root != "Trash" {
+		setFlash(w, "error", "Only a folder already in Trash can be permanently deleted")
+		http.Redirect(w, r, MailboxPrefix+"/mail/Trash", http.StatusFound)
+		return
+	}
+	n, err := a.deleteFolderSubtreePermanently(mbox, name, true)
+	if err != nil {
+		setFlash(w, "error", "Error deleting folder")
+	} else {
+		setFlash(w, "success", fmt.Sprintf("Folder %s permanently deleted (%d message(s))", name, n))
+	}
+	http.Redirect(w, r, MailboxPrefix+"/mail/Trash", http.StatusFound)
+}
+
+// webmailRestoreFolder puts a folder that's currently under Trash back where it was
+// before it was deleted (or under INBOX if that's no longer known — see
+// db.RestoreFolder). Only a folder currently under Trash can be restored this way.
+func (a *App) webmailRestoreFolder(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	name := r.PathValue("name")
+
+	if root, err := a.DB.FolderRoot(mbox.ID, name); err != nil || root != "Trash" {
+		setFlash(w, "error", "Only a folder in Trash can be restored")
+		http.Redirect(w, r, MailboxPrefix+"/mail/Trash", http.StatusFound)
+		return
+	}
+	if err := a.DB.RestoreFolder(mbox.ID, name); err != nil {
+		setFlash(w, "error", "Error restoring folder")
+	} else {
+		setFlash(w, "success", "Folder "+name+" restored")
+	}
+	http.Redirect(w, r, MailboxPrefix+"/mail/"+name, http.StatusFound)
+}
+
+// webmailToggleStar flips \Flagged on one message — the message list's star icon.
+func (a *App) webmailToggleStar(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	folder := r.PathValue("folder")
+	uid := int64(atoi(r.PathValue("uid")))
+	if _, ok := a.messageAccessible(mbox.ID, folder, uid); !ok {
+		http.NotFound(w, r)
+		return
+	}
+	if err := a.DB.ToggleMessageStarred(mbox.ID, uid); err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}
+
+// maxFolderOrderEntries bounds a single reorder request — the sidebar only ever
+// shows a handful of folders, so a much larger list is either a stale client or
+// something malformed, not a real drag-and-drop.
+const maxFolderOrderEntries = 200
+
+// webmailSetFolderOrder persists the sidebar's full drag-and-drop order — called
+// once per drag, with the complete current folder list top to bottom (see
+// db.SetFolderOrder). No redirect/flash: the client already reflects the order it
+// just dragged into place, this call is purely to persist it for next page load.
+func (a *App) webmailSetFolderOrder(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	if err := r.ParseForm(); err != nil {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+	order := r.Form["order"]
+	if len(order) == 0 || len(order) > maxFolderOrderEntries {
+		w.WriteHeader(http.StatusBadRequest)
+		return
+	}
+	for i, name := range order {
+		order[i] = strings.TrimSpace(name)
+		if order[i] == "" || len(order[i]) > maxFolderNameLen {
+			w.WriteHeader(http.StatusBadRequest)
+			return
+		}
+	}
+	if err := a.DB.SetFolderOrder(mbox.ID, order); err != nil {
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+	w.WriteHeader(http.StatusNoContent)
+}

internal/webui/webmail_signatures.go

@@ -0,0 +1,88 @@
+package webui
+
+import (
+	"net/http"
+	"strings"
+
+	"mailgoserver/internal/db"
+)
+
+// webmailSignaturesPage lists a mailbox's saved signatures and the add/edit form.
+func (a *App) webmailSignaturesPage(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	signatures, err := a.DB.ListSignatures(mbox.ID)
+	if err != nil {
+		setFlash(w, "error", "Error loading signatures")
+	}
+
+	// ?edit=<id> loads an existing signature into the form instead of a blank one.
+	var editing *db.MailboxSignature
+	if idStr := r.URL.Query().Get("edit"); idStr != "" {
+		editing, _ = a.DB.GetSignatureByID(mbox.ID, int64(atoi(idStr)))
+	}
+
+	a.render(w, r, "webmail_signatures.html", M{
+		"mailbox": mbox, "signatures": signatures, "editing": editing,
+		"flashes": popFlashes(w, r),
+	})
+}
+
+// webmailSignatureSave creates a new signature, or updates one when id (a hidden
+// form field, not a path segment — this is a single form reused for add and edit) is
+// set.
+func (a *App) webmailSignatureSave(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	if err := r.ParseForm(); err != nil {
+		setFlash(w, "error", "Invalid form data")
+		http.Redirect(w, r, MailboxPrefix+"/signatures", http.StatusFound)
+		return
+	}
+	name := strings.TrimSpace(r.FormValue("name"))
+	contentHTML := r.FormValue("content_html")
+	if name == "" {
+		setFlash(w, "error", "Give the signature a name")
+		http.Redirect(w, r, MailboxPrefix+"/signatures", http.StatusFound)
+		return
+	}
+
+	id := int64(atoi(r.FormValue("id")))
+	var err error
+	if id != 0 {
+		err = a.DB.UpdateSignature(mbox.ID, id, name, contentHTML)
+	} else {
+		_, err = a.DB.CreateSignature(mbox.ID, name, contentHTML)
+	}
+	if err != nil {
+		a.Logger.Error("save signature for mailbox %d: %v", mbox.ID, err)
+		setFlash(w, "error", "Could not save the signature")
+	} else {
+		setFlash(w, "success", "Signature saved")
+	}
+	http.Redirect(w, r, MailboxPrefix+"/signatures", http.StatusFound)
+}
+
+func (a *App) webmailSignatureDelete(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	id := int64(atoi(r.PathValue("id")))
+	if err := a.DB.DeleteSignature(mbox.ID, id); err != nil {
+		setFlash(w, "error", "Could not delete the signature")
+	} else {
+		setFlash(w, "success", "Signature deleted")
+	}
+	http.Redirect(w, r, MailboxPrefix+"/signatures", http.StatusFound)
+}
+
+// webmailSignatureSetDefault marks a signature (or, when id=0, clears the flag
+// entirely) as the mailbox's default for new messages or for reply/forward, per the
+// "which" form field ("new" or "reply").
+func (a *App) webmailSignatureSetDefault(w http.ResponseWriter, r *http.Request) {
+	mbox := mailboxFromContext(r)
+	id := int64(atoi(r.PathValue("id")))
+	forReply := r.URL.Query().Get("which") == "reply"
+	if err := a.DB.SetDefaultSignature(mbox.ID, id, forReply); err != nil {
+		setFlash(w, "error", "Could not update the default signature")
+	} else {
+		setFlash(w, "success", "Default signature updated")
+	}
+	http.Redirect(w, r, MailboxPrefix+"/signatures", http.StatusFound)
+}

internal/webui/webmail_signatures_test.go

@@ -0,0 +1,123 @@
+package webui
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"strconv"
+	"strings"
+	"testing"
+)
+
+// TestWebmailSignatureCreateEditDeleteAndDefaults exercises the full signature CRUD
+// flow plus setting/clearing the default-for-new and default-for-reply flags.
+func TestWebmailSignatureCreateEditDeleteAndDefaults(t *testing.T) {
+	app := newTestApp(t)
+	mux := app.Mux()
+	domains, _ := app.DB.ListDomains()
+	mailboxID := createTestMailboxWithPassword(t, app, "sigtest@example.com", domains[0].ID, "sigtest-password-1!")
+	cookie := webmailLoginSession(t, app, mailboxID)
+
+	save := func(id, name, html string) *httptest.ResponseRecorder {
+		form := url.Values{"id": {id}, "name": {name}, "content_html": {html}}
+		req := httptest.NewRequest(http.MethodPost, MailboxPrefix+"/signatures/save", strings.NewReader(form.Encode()))
+		req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+		req.AddCookie(cookie)
+		rec := httptest.NewRecorder()
+		mux.ServeHTTP(rec, req)
+		return rec
+	}
+
+	if rec := save("", "Work", "<p>Jane Doe<br>Acme Inc</p>"); rec.Code != http.StatusFound {
+		t.Fatalf("create: status=%d body=%s", rec.Code, rec.Body.String())
+	}
+	sigs, err := app.DB.ListSignatures(mailboxID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(sigs) != 1 || sigs[0].Name != "Work" {
+		t.Fatalf("expected 1 signature named Work, got %+v", sigs)
+	}
+	id := sigs[0].ID
+
+	// Edit it.
+	if rec := save(strconv.FormatInt(id, 10), "Work Updated", "<p>Jane Doe, CEO</p>"); rec.Code != http.StatusFound {
+		t.Fatalf("edit: status=%d body=%s", rec.Code, rec.Body.String())
+	}
+	updated, err := app.DB.GetSignatureByID(mailboxID, id)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if updated == nil || updated.Name != "Work Updated" || !strings.Contains(updated.ContentHTML, "CEO") {
+		t.Fatalf("expected updated signature, got %+v", updated)
+	}
+
+	// Set as default for both new and reply.
+	for _, which := range []string{"new", "reply"} {
+		req := httptest.NewRequest(http.MethodPost, MailboxPrefix+"/signatures/"+strconv.FormatInt(id, 10)+"/default?which="+which, nil)
+		req.AddCookie(cookie)
+		rec := httptest.NewRecorder()
+		mux.ServeHTTP(rec, req)
+		if rec.Code != http.StatusFound {
+			t.Fatalf("set default %s: status=%d body=%s", which, rec.Code, rec.Body.String())
+		}
+	}
+	got, err := app.DB.GetSignatureByID(mailboxID, id)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !got.IsDefaultNew || !got.IsDefaultReply {
+		t.Fatalf("expected both defaults set, got %+v", got)
+	}
+	def, err := app.DB.GetDefaultSignature(mailboxID, false)
+	if err != nil || def == nil || def.ID != id {
+		t.Fatalf("GetDefaultSignature(new) = %+v, err=%v", def, err)
+	}
+
+	// Delete it — defaults should just disappear along with the row.
+	delReq := httptest.NewRequest(http.MethodPost, MailboxPrefix+"/signatures/"+strconv.FormatInt(id, 10)+"/delete", nil)
+	delReq.AddCookie(cookie)
+	delRec := httptest.NewRecorder()
+	mux.ServeHTTP(delRec, delReq)
+	if delRec.Code != http.StatusFound {
+		t.Fatalf("delete: status=%d body=%s", delRec.Code, delRec.Body.String())
+	}
+	remaining, err := app.DB.ListSignatures(mailboxID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(remaining) != 0 {
+		t.Fatalf("expected no signatures left, got %+v", remaining)
+	}
+}
+
+// TestWebmailSignatureOnlyOneDefaultPerMailbox confirms setting a second signature as
+// the default-for-new clears the flag from whichever one had it before.
+func TestWebmailSignatureOnlyOneDefaultPerMailbox(t *testing.T) {
+	app := newTestApp(t)
+	domains, _ := app.DB.ListDomains()
+	mailboxID := createTestMailboxWithPassword(t, app, "sigdefault@example.com", domains[0].ID, "sigdefault-password-1!")
+
+	id1, err := app.DB.CreateSignature(mailboxID, "One", "<p>1</p>")
+	if err != nil {
+		t.Fatal(err)
+	}
+	id2, err := app.DB.CreateSignature(mailboxID, "Two", "<p>2</p>")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := app.DB.SetDefaultSignature(mailboxID, id1, false); err != nil {
+		t.Fatal(err)
+	}
+	if err := app.DB.SetDefaultSignature(mailboxID, id2, false); err != nil {
+		t.Fatal(err)
+	}
+	s1, _ := app.DB.GetSignatureByID(mailboxID, id1)
+	s2, _ := app.DB.GetSignatureByID(mailboxID, id2)
+	if s1.IsDefaultNew {
+		t.Error("expected signature 1 to no longer be the default")
+	}
+	if !s2.IsDefaultNew {
+		t.Error("expected signature 2 to now be the default")
+	}
+}

internal/webui/webui.go

@@ -162,14 +162,27 @@ func (a *App) Mux() *http.ServeMux {
 	webmailMux.HandleFunc("GET "+MailboxPrefix+"/mail/{folder}/{uid}/pane", a.webmailMessagePane)
 	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/{folder}/{uid}/delete", a.webmailMessageDelete)
 	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/{folder}/{uid}/move", a.webmailMessageMove)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/{folder}/{uid}/star", a.webmailToggleStar)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/{folder}/{uid}/restore", a.webmailRestoreMessage)
 	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/{folder}/bulk", a.webmailBulkAction)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/{folder}/mark-all-read", a.webmailMarkAllRead)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/{folder}/empty", a.webmailEmptyTrash)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/{folder}/clean-spam", a.webmailCleanSpam)
 	webmailMux.HandleFunc("GET "+MailboxPrefix+"/mail/{folder}/{uid}/attachment/{idx}", a.webmailAttachmentDownload)
 	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/folders/add", a.webmailAddFolder)
 	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/folders/{name}/remove", a.webmailDeleteFolder)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/folders/{name}/rename", a.webmailRenameFolder)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/folders/{name}/delete-permanently", a.webmailDeleteFolderPermanently)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/folders/{name}/restore", a.webmailRestoreFolder)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/mail/folders/order", a.webmailSetFolderOrder)
 
 	webmailMux.HandleFunc("GET "+MailboxPrefix+"/rules", a.webmailRulesList)
 	webmailMux.HandleFunc("POST "+MailboxPrefix+"/rules/add", a.webmailAddRule)
 	webmailMux.HandleFunc("POST "+MailboxPrefix+"/rules/{rule_id}/remove", a.webmailRemoveRule)
+	webmailMux.HandleFunc("GET "+MailboxPrefix+"/signatures", a.webmailSignaturesPage)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/signatures/save", a.webmailSignatureSave)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/signatures/{id}/delete", a.webmailSignatureDelete)
+	webmailMux.HandleFunc("POST "+MailboxPrefix+"/signatures/{id}/default", a.webmailSignatureSetDefault)
 	webmailMux.HandleFunc("GET "+MailboxPrefix+"/certs", a.webmailCertsPage)
 	webmailMux.HandleFunc("POST "+MailboxPrefix+"/smime/identity/generate", a.webmailSMIMEGenerate)
 	webmailMux.HandleFunc("POST "+MailboxPrefix+"/smime/identity/import", a.webmailSMIMEImport)