Font picker fix round: one search field, honest empty-enumeration fallback, tooltip only on the closed trigger

- FontMenuList: the separate custom-family input is gone; the search
  field absorbed its job — a no-match query renders a 'Use <query>'
  action row (customFamilyFor, pure, pinned), Enter picks it
- openFontMenu: an empty-but-successful queryLocalFonts() now falls back
  to the curated list (Electron 44 grants local-fonts and still
  enumerates zero fonts — reproduced with a hidden-Window probe); the
  footer split states WHY: 'could not be read' vs 'needs the desktop app'
- The Hint tooltip wraps the trigger button only and unmounts while the
  menu is open — it no longer pops over the dropdown

components/settings/appearance-section.tsx

@@ -97,32 +97,49 @@ export function AppearanceSection({
 
 	// The font dropdown's open state + its enumeration cache. undefined =
 	// not enumerated yet (desktop: click-bound queryLocalFonts pending);
-	// null = the API is absent (dev browser → the curated fallback, footed
-	// honestly); a list = the deduped families.
+	// null = enumeration UNAVAILABLE (the API is absent in a plain
+	// browser, rejected, or resolved EMPTY — Electron 44's local-fonts
+	// grant passes and the enumeration still yields zero fonts,
+	// reproduced 2026-09-26) → the curated fallback; a list = the deduped
+	// families. enumEmpty distinguishes WHY it fell back, for the footer.
 	const [fontMenuOpen, setFontMenuOpen] = useState(false);
 	const [localFonts, setLocalFonts] = useState<string[] | null | undefined>(undefined);
+	const [enumEmpty, setEnumEmpty] = useState(false);
 	const menuAnchorRef = useRef<HTMLSpanElement>(null);
 
 	// The enumeration runs INSIDE the trigger click — queryLocalFonts
 	// requires user activation, so it cannot be a mount effect. First
 	// open only: the families are cached for the section's life (font
-	// installs mid-dialog are not a case); a failed enumeration falls
-	// back to the curated list rather than an empty picker.
+	// installs mid-dialog are not a case); ANY unavailable enumeration
+	// (absent / rejected / empty) falls back to the curated list rather
+	// than an empty picker.
 	const openFontMenu = () => {
 		setFontMenuOpen((open) => {
 			if (!open && localFonts === undefined) {
 				const api = localFontsApi();
 				if (api === null) {
 					setLocalFonts(null);
+					setEnumEmpty(false);
 				} else {
 					void api()
 						.then((fonts) => {
 							const families = [...new Set(fonts.map((f) => f.family))]
 								.filter((f) => f !== DEFAULT_READING_FONT)
 								.sort((a, b) => a.localeCompare(b));
-							setLocalFonts(families);
+							if (families.length === 0) {
+								// Resolved-but-empty: not a failure the catch sees —
+								// an honest unavailable (this Electron 44 build
+								// enumerates nothing even granted).
+								setLocalFonts(null);
+								setEnumEmpty(true);
+							} else {
+								setLocalFonts(families);
+							}
 						})
-						.catch(() => setLocalFonts(null));
+						.catch(() => {
+							setLocalFonts(null);
+							setEnumEmpty(false);
+						});
 				}
 			}
 			return !open;
@@ -187,48 +204,63 @@ export function AppearanceSection({
 				hint={`Empty = ${DEFAULT_READING_FONT}`}
 				testid="row-font"
 			>
-				<Hint label="Choose from your installed fonts" side="left">
-					<span ref={fontMenuOpen ? menuAnchorRef : undefined} className="relative flex items-center gap-2">
-						{/* The MenuTrigger look (agent-section's collapsed
-						    select — it lives unexported there, so the
-						    classes ride inline; the searchable machine is
-						    the shared part). */}
-						<button
-							type="button"
-							aria-label="Reading font"
-							aria-expanded={fontMenuOpen}
-							data-testid="font-trigger"
-							onClick={openFontMenu}
-							className="flex h-7 min-w-20 items-center gap-1 rounded-sm border border-border bg-background px-1.5 font-ui text-xs text-foreground transition-colors hover:border-muted-foreground/50"
-						>
-							<span className="min-w-0 flex-1 truncate">{appearance?.fontFamily || DEFAULT_READING_FONT}</span>
-							<span aria-hidden className="text-muted-foreground">
-								▾
-							</span>
-						</button>
-						{fontMenuOpen && (
-							<MenuShell
-								preferredSide="down"
-								anchorTestid="font-trigger"
-								testid="font-menu"
-								menuClass="flex w-[18rem] flex-col gap-0.5 rounded-xl border border-border bg-card p-2 text-xs shadow-xl"
+				<span ref={fontMenuOpen ? menuAnchorRef : undefined} className="relative flex items-center gap-2">
+					{/* The MenuTrigger look (agent-section's collapsed
+					    select — it lives unexported there, so the
+					    classes ride inline; the searchable machine is
+					    the shared part). The tooltip rides the CLOSED
+					    button ONLY (owner ruling 2026-09-26: never while
+					    the dropdown is out — it popped over the open
+					    menu when the wrap covered the whole anchor
+					    span). */}
+					{(() => {
+						const triggerButton = (
+							<button
+								type="button"
+								aria-label="Reading font"
+								aria-expanded={fontMenuOpen}
+								data-testid="font-trigger"
+								onClick={openFontMenu}
+								className="flex h-7 min-w-20 items-center gap-1 rounded-sm border border-border bg-background px-1.5 font-ui text-xs text-foreground transition-colors hover:border-muted-foreground/50"
 							>
-								<FontMenuList
-									families={localFonts === undefined ? undefined : (localFonts ?? [...CURATED_FALLBACK_FONTS])}
-									effectiveFamily={appearance?.fontFamily ?? null}
-									onPick={pickFont}
-									footer={
-										localFonts === undefined
-											? undefined
-											: localFonts === null
-												? "Common families — your installed list needs the desktop app"
-												: "Your installed fonts"
-									}
-								/>
-							</MenuShell>
-						)}
-					</span>
-				</Hint>
+								<span className="min-w-0 flex-1 truncate">{appearance?.fontFamily || DEFAULT_READING_FONT}</span>
+								<span aria-hidden className="text-muted-foreground">
+									▾
+								</span>
+							</button>
+						);
+						return fontMenuOpen ? (
+							triggerButton
+						) : (
+							<Hint label="Choose from your installed fonts" side="left">
+								{triggerButton}
+							</Hint>
+						);
+					})()}
+					{fontMenuOpen && (
+						<MenuShell
+							preferredSide="down"
+							anchorTestid="font-trigger"
+							testid="font-menu"
+							menuClass="flex w-[18rem] flex-col gap-0.5 rounded-xl border border-border bg-card p-2 text-xs shadow-xl"
+						>
+							<FontMenuList
+								families={localFonts === undefined ? undefined : (localFonts ?? [...CURATED_FALLBACK_FONTS])}
+								effectiveFamily={appearance?.fontFamily ?? null}
+								onPick={pickFont}
+								footer={
+									localFonts === undefined
+										? undefined
+										: localFonts === null
+											? enumEmpty
+												? "Common families — installed fonts could not be read"
+												: "Common families — your installed list needs the desktop app"
+											: "Your installed fonts"
+								}
+							/>
+						</MenuShell>
+					)}
+				</span>
 			</SettingsRow>
 			<SettingsRow label="Reading font size" hint={`${resolved.proseFontSize}px`} testid="row-prose-size">
 				<CommitInput