diff --git a/shells/desktop/src/system-ui/app.tsx b/shells/desktop/src/system-ui/app.tsx
index cfa5648..d8b508e 100644
--- a/shells/desktop/src/system-ui/app.tsx
+++ b/shells/desktop/src/system-ui/app.tsx
@@ -31,6 +31,7 @@ import { Image, View } from "@pocketjs/framework/components";
 import { onFrame } from "@pocketjs/framework/lifecycle";
 import { virtualNow } from "@pocketjs/framework/clock";
 import { connectSvc, type CursorKind, type HostEvent } from "./svc.ts";
+import { applyLang, appTitle, lw } from "./words.ts";
 import {
   cascadePos,
   clampMove,
@@ -149,7 +150,7 @@ import {
 } from "./chrome.tsx";
 
 /** Label of every About entry and the About window's title. */
-const ABOUT_LABEL = `About ${DESKTOP_NAME}`;
+const aboutLabel = () => lw().about(DESKTOP_NAME);
 
 const WELCOME = [
   `Welcome to ${DESKTOP_NAME}.`,
@@ -364,6 +365,7 @@ export default function App() {
 
   function closeWin(id: number) {
     layouts.get(id)?.dispose(); layouts.delete(id);
+    padNames.delete(id);
     wins.set(wins().filter((w) => w.id !== id));
     stack = stack.filter((x) => x !== id);
     applyZ();
@@ -464,7 +466,13 @@ export default function App() {
 
   // ---- programs ---------------------------------------------------------------
 
-  function openNotepad(title: string, content: string[]) {
+  /** Each Notepad window's document name; null for an untitled one. The
+   *  window's title is made from it, again when the language changes. */
+  const padNames = new Map<number, string | null>();
+  const padTitle = (name: string | null) => lw().notepadTitle(name ?? lw().untitled);
+
+  function openNotepad(name: string | null, content: string[]) {
+    const title = padTitle(name);
     const existing = wins().find(
       (w) => w.kind === "notepad" && w.title() === title,
     );
@@ -497,11 +505,11 @@ export default function App() {
       minH: 140,
       menus: [
         {
-          label: "File",
-          width: menuW("File"),
+          label: lw().file,
+          width: menuW(lw().file),
           items: () => [
             {
-              label: "New",
+              label: lw().new,
               act: () => {
                 applyEdit(w, "other", {
                   lines: [""],
@@ -511,7 +519,7 @@ export default function App() {
             },
             { sep: true, label: "" },
             {
-              label: "Exit",
+              label: lw().exit,
               shortcut: "Cmd+W",
               act: () => {
                 closeWin(w.id);
@@ -520,11 +528,11 @@ export default function App() {
           ],
         },
         {
-          label: "Edit",
-          width: menuW("Edit"),
+          label: lw().edit,
+          width: menuW(lw().edit),
           items: () => [
             {
-              label: "Undo",
+              label: lw().undo,
               shortcut: "Cmd+Z",
               disabled: data.hist.undo.length === 0,
               act: () => {
@@ -532,7 +540,7 @@ export default function App() {
               },
             },
             {
-              label: "Redo",
+              label: lw().redo,
               shortcut: "Cmd+Shift+Z",
               disabled: data.hist.redo.length === 0,
               act: () => {
@@ -541,20 +549,20 @@ export default function App() {
             },
             { sep: true, label: "" },
             {
-              label: "Cut",
+              label: lw().cut,
               shortcut: "Cmd+X",
               disabled: !hasSel(data.doc()),
               act: cutSel,
             },
             {
-              label: "Copy",
+              label: lw().copy,
               shortcut: "Cmd+C",
               disabled: !hasSel(data.doc()),
               act: copySel,
             },
-            { label: "Paste", shortcut: "Cmd+V", act: pasteReq },
+            { label: lw().paste, shortcut: "Cmd+V", act: pasteReq },
             {
-              label: "Select All",
+              label: lw().selectAll,
               shortcut: "Cmd+A",
               act: () => {
                 selectAllIn(w);
@@ -562,7 +570,7 @@ export default function App() {
             },
             { sep: true, label: "" },
             {
-              label: "Time/Date",
+              label: lw().timeDate,
               shortcut: "F5",
               act: () => {
                 insertTimeDate(w);
@@ -570,7 +578,7 @@ export default function App() {
             },
             { sep: true, label: "" },
             {
-              label: "Word Wrap",
+              label: lw().wordWrap,
               checked: data.wrap(),
               act: () => {
                 data.wrap.set(!data.wrap());
@@ -580,14 +588,15 @@ export default function App() {
           ],
         },
         {
-          label: "Help",
-          width: menuW("Help"),
-          items: () => [{ label: ABOUT_LABEL, act: openAbout }],
+          label: lw().help,
+          width: menuW(lw().help),
+          items: () => [{ label: aboutLabel(), act: openAbout }],
         },
       ],
       data,
     });
     layouts.set(w.id, createPadLayout(w));
+    padNames.set(w.id, name);
     addWin(w);
   }
 
@@ -604,14 +613,14 @@ export default function App() {
     const outer = reframeGeo(
       { x: 0, y: 0, w: MINES_GEO.w, h: MINES_GEO.h },
       {
-        menuWidths: [menuW("Game"), menuW("Help")],
+        menuWidths: [menuW(lw().game), menuW(lw().help)],
       },
       CLASSIC_THEME.metrics,
       metrics(),
     );
     const w = createWin({
       kind: "mines",
-      title: "Minesweeper",
+      title: lw().minesweeper,
       icon: "mines",
       geo: {
         ...cascadePos(
@@ -627,11 +636,11 @@ export default function App() {
       resizable: false,
       menus: [
         {
-          label: "Game",
-          width: menuW("Game"),
+          label: lw().game,
+          width: menuW(lw().game),
           items: () => [
             {
-              label: "New",
+              label: lw().new,
               shortcut: "F2",
               act: () => {
                 minesNew(w);
@@ -639,7 +648,7 @@ export default function App() {
             },
             { sep: true, label: "" },
             {
-              label: "Exit",
+              label: lw().exit,
               shortcut: "Cmd+W",
               act: () => {
                 closeWin(w.id);
@@ -648,9 +657,9 @@ export default function App() {
           ],
         },
         {
-          label: "Help",
-          width: menuW("Help"),
-          items: () => [{ label: ABOUT_LABEL, act: openAbout }],
+          label: lw().help,
+          width: menuW(lw().help),
+          items: () => [{ label: aboutLabel(), act: openAbout }],
         },
       ],
       data,
@@ -675,7 +684,7 @@ export default function App() {
       app.viewport[1] + contentTop({ menuWidths: [] }, m) + m.frame;
     const w = createWin({
       kind: "pocket",
-      title: appWindowTitle(app.title),
+      title: appWindowTitle(appTitle(app)),
       icon: "pocket",
       geo: cascadePos(
         wins().length,
@@ -711,37 +720,37 @@ export default function App() {
             icon: "drive",
             name: "(C:)",
             size: "",
-            type: "Local Disk",
+            type: lw().localDisk,
             open: () => {
               navigate(w, "drivec");
             },
           },
-          { icon: "cdrom", name: "(D:)", size: "", type: "CD-ROM Disc" },
-          { icon: "folder", name: "Control Panel", size: "", type: "System Folder" },
-          { icon: "folder", name: "Printers", size: "", type: "System Folder" },
+          { icon: "cdrom", name: "(D:)", size: "", type: lw().cdromDisc },
+          { icon: "folder", name: lw().controlPanel, size: "", type: lw().systemFolder },
+          { icon: "folder", name: lw().printers, size: "", type: lw().systemFolder },
         ];
       case "drivec":
         return [
-          { icon: "folder", name: "Program Files", size: "", type: "File Folder" },
-          { icon: "folder", name: "System", size: "", type: "File Folder" },
+          { icon: "folder", name: "Program Files", size: "", type: lw().fileFolder },
+          { icon: "folder", name: "System", size: "", type: lw().fileFolder },
           {
             icon: "folder",
-            name: "My Documents",
+            name: lw().myDocuments,
             size: "",
-            type: "File Folder",
+            type: lw().fileFolder,
             open: () => {
               navigate(w, "documents");
             },
           },
-          { icon: "file", name: "AUTOEXEC.BAT", size: "1 KB", type: "Batch File" },
-          { icon: "file", name: "CONFIG.SYS", size: "1 KB", type: "System file" },
+          { icon: "file", name: "AUTOEXEC.BAT", size: "1 KB", type: lw().batchFile },
+          { icon: "file", name: "CONFIG.SYS", size: "1 KB", type: lw().systemFile },
           {
             icon: "notepad",
             name: "README.TXT",
             size: "2 KB",
-            type: "Text Document",
+            type: lw().textDocument,
             open: () => {
-              openNotepad("README.TXT - Notepad", WELCOME);
+              openNotepad("README.TXT", WELCOME);
             },
           },
         ];
@@ -751,9 +760,9 @@ export default function App() {
             icon: "notepad",
             name: "welcome.txt",
             size: "1 KB",
-            type: "Text Document",
+            type: lw().textDocument,
             open: () => {
-              openNotepad("welcome.txt - Notepad", WELCOME);
+              openNotepad("welcome.txt", WELCOME);
             },
           },
         ];
@@ -766,6 +775,14 @@ export default function App() {
     return PLACES.find((p) => p.id === id) ?? PLACES[0];
   }
 
+  /** A place's name in the active language: its window's title and its sidebar entry. */
+  function placeLabel(id: PlaceId): string {
+    if (id === "computer") return lw().myComputer;
+    if (id === "documents") return lw().myDocuments;
+    if (id === "recycle") return lw().recycleBin;
+    return placeOf(id).label;
+  }
+
   /** Point a folder window at another place: title, icon, rows, selection.
    *  Pushes onto the history unless the move IS a history step. */
   function navigate(w: WinCtl, id: PlaceId, push = true) {
@@ -778,7 +795,7 @@ export default function App() {
     d.place.set(id);
     d.rows.set(placeRows(id, w));
     d.selected.set(-1);
-    w.title.set(place.label);
+    w.title.set(placeLabel(id));
     w.icon.set(place.icon);
   }
 
@@ -820,7 +837,7 @@ export default function App() {
     };
     const w = createWin({
       kind: "folder",
-      title: place.label,
+      title: placeLabel(id),
       icon: place.icon,
       geo: cascadePos(wins().length, vp().w, vp().h, 560, 320, metrics()),
       minW: 380,
@@ -841,7 +858,7 @@ export default function App() {
     const data: AboutData = { kind: "about", armed: createState<string | null>(null) };
     const w = createWin({
       kind: "about",
-      title: ABOUT_LABEL,
+      title: aboutLabel(),
       icon: "computer",
       geo: centered(ABOUT_GEO.w, ABOUT_GEO.h),
       buttons: ["close"],
@@ -864,7 +881,7 @@ export default function App() {
       // No name after the verb: the dialog is 300px wide, and Aqua's
       // centered caption has room for about twenty characters between its
       // control cluster and the balancing spacer.
-      title: "Shut Down",
+      title: lw().shutDown,
       icon: "shutdown",
       geo: centered(SHUTDOWN_GEO.w, SHUTDOWN_GEO.h),
       buttons: ["close"],
@@ -907,21 +924,22 @@ export default function App() {
 
   // ---- desktop icons + start menu ----------------------------------------------
 
-  const icons: DeskIcon[] = [
-    { icon: "computer", label: "My Computer", open: openMyComputer },
-    { icon: "documents", label: "My Documents", open: openDocuments },
-    { icon: "recycle", label: "Recycle Bin", open: openRecycle },
+  /** The desktop's icons, labelled in the active language. */
+  const icons = (): DeskIcon[] => [
+    { icon: "computer", label: lw().myComputer, open: openMyComputer },
+    { icon: "documents", label: lw().myDocuments, open: openDocuments },
+    { icon: "recycle", label: lw().recycleBin, open: openRecycle },
     {
       icon: "notepad",
-      label: "Notepad",
+      label: lw().notepad,
       open: () => {
-        openNotepad("Untitled - Notepad", [""]);
+        openNotepad(null, [""]);
       },
     },
-    { icon: "mines", label: "Minesweeper", open: openMines },
+    { icon: "mines", label: lw().minesweeper, open: openMines },
     ...POCKET_APPS.map((app): DeskIcon => ({
       icon: "pocket",
-      label: app.title,
+      label: appTitle(app),
       open: () => openPocketApp(app),
     })),
   ];
@@ -930,7 +948,7 @@ export default function App() {
     return desktopIconAt(
       x,
       y,
-      icons.length,
+      icons().length,
       desktopIconRows(vp().h, metrics()),
       metrics(),
       vp().w,
@@ -941,15 +959,15 @@ export default function App() {
    *  panel's "All Programs" share one list. */
   const programItems = (): PopupItem[] => [
     {
-      label: "Notepad",
+      label: lw().notepad,
       icon: "notepad",
       act: () => {
-        openNotepad("Untitled - Notepad", [""]);
+        openNotepad(null, [""]);
       },
     },
-    { label: "Minesweeper", icon: "mines", act: openMines },
+    { label: lw().minesweeper, icon: "mines", act: openMines },
     ...POCKET_APPS.map((app): PopupItem => ({
-      label: app.title,
+      label: appTitle(app),
       icon: "pocket",
       act: () => openPocketApp(app),
     })),
@@ -969,7 +987,7 @@ export default function App() {
       label: "welcome.txt",
       icon: "notepad",
       act: () => {
-        openNotepad("welcome.txt - Notepad", WELCOME);
+        openNotepad("welcome.txt", WELCOME);
       },
     },
   ];
@@ -978,60 +996,60 @@ export default function App() {
    *  system entries on the right, Turn Off Computer in the bottom strip. */
   const xpStartItems = (): PopupItem[] => [
     {
-      label: "Notepad",
+      label: lw().notepad,
       icon: "notepad",
       act: () => {
-        openNotepad("Untitled - Notepad", [""]);
+        openNotepad(null, [""]);
       },
     },
-    { label: "Minesweeper", icon: "mines", act: openMines },
+    { label: lw().minesweeper, icon: "mines", act: openMines },
     { sep: true, label: "" },
     ...POCKET_APPS.slice(0, 5).map((app): PopupItem => ({
-      label: app.title,
+      label: appTitle(app),
       icon: "pocket",
       act: () => openPocketApp(app),
     })),
     { sep: true, label: "", bottom: true },
     {
-      label: "All Programs",
+      label: lw().allPrograms,
       icon: "folder",
       bottom: true,
       sub: programItems(),
     },
     {
-      label: "My Documents",
+      label: lw().myDocuments,
       icon: "folder",
       col: "right",
       sub: documentItems(),
     },
     {
-      label: "My Computer",
+      label: lw().myComputer,
       icon: "computer",
       col: "right",
       act: openMyComputer,
     },
     { sep: true, label: "", col: "right" },
     {
-      label: "Settings",
+      label: lw().settings,
       icon: "settings",
       col: "right",
       sub: themeItems(),
     },
     {
-      label: "Help",
+      label: lw().help,
       icon: "help",
       col: "right",
       act: openAbout,
     },
     { sep: true, label: "", col: "right" },
     {
-      label: "Run...",
+      label: lw().run,
       icon: "run",
       col: "right",
       disabled: true,
     },
     {
-      label: "Turn Off Computer",
+      label: lw().turnOff,
       icon: "power",
       foot: true,
       act: openShutdown,
@@ -1040,39 +1058,39 @@ export default function App() {
 
   const classicStartItems = (): PopupItem[] => [
     {
-      label: "Programs",
+      label: lw().programs,
       icon: "folder",
       sub: [
         {
-          label: "Notepad",
+          label: lw().notepad,
           icon: "notepad",
           act: () => {
-            openNotepad("Untitled - Notepad", [""]);
+            openNotepad(null, [""]);
           },
         },
-        { label: "Minesweeper", icon: "mines", act: openMines },
+        { label: lw().minesweeper, icon: "mines", act: openMines },
         ...POCKET_APPS.map((app): PopupItem => ({
-          label: app.title,
+          label: appTitle(app),
           icon: "pocket",
           act: () => openPocketApp(app),
         })),
       ],
     },
     {
-      label: "Documents",
+      label: lw().documents,
       icon: "folder",
       sub: [
         {
           label: "welcome.txt",
           icon: "notepad",
           act: () => {
-            openNotepad("welcome.txt - Notepad", WELCOME);
+            openNotepad("welcome.txt", WELCOME);
           },
         },
       ],
     },
     {
-      label: "Settings",
+      label: lw().settings,
       icon: "settings",
       sub: THEMES.map((item) => ({
         label: item.label,
@@ -1082,25 +1100,25 @@ export default function App() {
         },
       })),
     },
-    { label: "Find", icon: "find", disabled: true },
-    { label: "Help", icon: "help", act: openAbout },
-    { label: "Run...", icon: "run", disabled: true },
+    { label: lw().find, icon: "find", disabled: true },
+    { label: lw().help, icon: "help", act: openAbout },
+    { label: lw().run, icon: "run", disabled: true },
     { sep: true, label: "" },
-    { label: "Shut Down...", icon: "shutdown", act: openShutdown },
+    { label: lw().shutDownMenu, icon: "shutdown", act: openShutdown },
   ];
 
   /** Aqua's logo menu: About first, the places and the theme picker, the
    *  session commands last — the shape of the menu under the mark. */
   const aquaStartItems = (): PopupItem[] => [
-    { label: ABOUT_LABEL, act: openAbout },
+    { label: aboutLabel(), act: openAbout },
     { sep: true, label: "" },
-    { label: "Programs", icon: "folder", sub: programItems() },
-    { label: "Documents", icon: "documents", sub: documentItems() },
-    { label: "My Computer", icon: "computer", act: openMyComputer },
+    { label: lw().programs, icon: "folder", sub: programItems() },
+    { label: lw().documents, icon: "documents", sub: documentItems() },
+    { label: lw().myComputer, icon: "computer", act: openMyComputer },
     { sep: true, label: "" },
-    { label: "Settings", icon: "settings", sub: themeItems() },
+    { label: lw().settings, icon: "settings", sub: themeItems() },
     { sep: true, label: "" },
-    { label: "Shut Down...", icon: "shutdown", act: openShutdown },
+    { label: lw().shutDownMenu, icon: "shutdown", act: openShutdown },
   ];
 
   const startItems = (): PopupItem[] => {
@@ -1185,10 +1203,10 @@ export default function App() {
    *  when nothing is focused. */
   function appNameOf(w: WinCtl | undefined): string {
     if (!w) return DESKTOP_NAME;
-    if (w.kind === "notepad") return "Notepad";
-    if (w.kind === "mines") return "Minesweeper";
-    if (w.kind === "folder") return "Files";
-    if (w.kind === "pocket") return pocketOf(w).app.title;
+    if (w.kind === "notepad") return lw().notepad;
+    if (w.kind === "mines") return lw().minesweeper;
+    if (w.kind === "folder") return lw().files;
+    if (w.kind === "pocket") return appTitle(pocketOf(w).app);
     return DESKTOP_NAME;
   }
 
@@ -1424,7 +1442,7 @@ export default function App() {
     const icon = iconAt(mx, my);
     iconSel.set(icon);
     focusId.set(-1);
-    if (icon >= 0 && isDblClick(`icon:${icon}`)) icons[icon].open();
+    if (icon >= 0 && isDblClick(`icon:${icon}`)) icons()[icon].open();
   }
 
   function routeContentDown(w: WinCtl, cx: number, cy: number, shift: boolean) {
@@ -1537,12 +1555,12 @@ export default function App() {
         const has = hasSel(d.doc());
         popup.set({
           popup: buildPopup(mx, my, [
-            { label: "Cut", shortcut: "Cmd+X", disabled: !has, act: cutSel },
-            { label: "Copy", shortcut: "Cmd+C", disabled: !has, act: copySel },
-            { label: "Paste", shortcut: "Cmd+V", act: pasteReq },
+            { label: lw().cut, shortcut: "Cmd+X", disabled: !has, act: cutSel },
+            { label: lw().copy, shortcut: "Cmd+C", disabled: !has, act: copySel },
+            { label: lw().paste, shortcut: "Cmd+V", act: pasteReq },
             { sep: true, label: "" },
             {
-              label: "Select All",
+              label: lw().selectAll,
               shortcut: "Cmd+A",
               act: () => {
                 selectAllIn(w);
@@ -1557,14 +1575,14 @@ export default function App() {
         popup.set({
           popup: buildPopup(mx, my, [
             {
-              label: "Minimize",
+              label: lw().minimize,
               shortcut: "Cmd+M",
               act: () => {
                 minimize(w.id);
               },
             },
             {
-              label: w.maximized() ? "Restore" : "Maximize",
+              label: w.maximized() ? lw().restore : lw().maximize,
               disabled: !w.resizable,
               act: () => {
                 toggleMax(w);
@@ -1572,7 +1590,7 @@ export default function App() {
             },
             { sep: true, label: "" },
             {
-              label: "Close",
+              label: lw().close,
               shortcut: "Cmd+W",
               act: () => {
                 closeWin(w.id);
@@ -1589,17 +1607,17 @@ export default function App() {
       iconSel.set(icon);
       popup.set({
         popup: buildPopup(mx, my, [
-          { label: "Arrange Icons", act: () => {} },
-          { label: "Refresh", act: () => {} },
+          { label: lw().arrangeIcons, act: () => {} },
+          { label: lw().refresh, act: () => {} },
           { sep: true, label: "" },
           {
-            label: "New Text Document",
+            label: lw().newTextDocument,
             act: () => {
-              openNotepad("Untitled - Notepad", [""]);
+              openNotepad(null, [""]);
             },
           },
           { sep: true, label: "" },
-          { label: "Properties", disabled: true },
+          { label: lw().properties, disabled: true },
         ]),
       });
     }
@@ -1900,7 +1918,7 @@ export default function App() {
         cycleWindows();
         return;
       case "n":
-        openNotepad("Untitled - Notepad", [""]);
+        openNotepad(null, [""]);
         return;
       case "w": {
         const w = focused();
@@ -2177,11 +2195,30 @@ export default function App() {
         if (isThemeId(ev.id)) setTheme(ev.id);
         break;
       }
+      case "lang": {
+        // The host names the language and its apps' titles in it. Labels
+        // read the catalog as they draw; window titles were set when each
+        // window opened, so they are made again here.
+        if (applyLang(ev.id, ev.titles)) retitleWindows();
+        break;
+      }
+    }
+  }
+
+  /** Give every open window its title in the active language. */
+  function retitleWindows() {
+    for (const win of wins()) {
+      if (win.kind === "pocket") win.title.set(appWindowTitle(appTitle(pocketOf(win).app)));
+      else if (win.kind === "notepad") win.title.set(padTitle(padNames.get(win.id) ?? null));
+      else if (win.kind === "mines") win.title.set(lw().minesweeper);
+      else if (win.kind === "folder") win.title.set(placeLabel(folderOf(win).place()));
+      else if (win.kind === "about") win.title.set(aboutLabel());
+      else if (win.kind === "shutdown") win.title.set(lw().shutDown);
     }
   }
 
   function boot() {
-    openNotepad("welcome.txt - Notepad", WELCOME);
+    openNotepad("welcome.txt", WELCOME);
     if (!svc) {
       // Standalone (sim, goldens): a lively static arrangement.
       openMines();
@@ -2254,7 +2291,7 @@ export default function App() {
         <View class={cls} />
       ))}
       <DesktopIcons
-        icons={icons}
+        icons={icons()}
         selected={iconSel()}
         rows={desktopIconRows(vp().h, metrics())}
         viewportW={vp().w}
diff --git a/shells/desktop/src/system-ui/chrome.tsx b/shells/desktop/src/system-ui/chrome.tsx
index 308e5dd..2f390b4 100644
--- a/shells/desktop/src/system-ui/chrome.tsx
+++ b/shells/desktop/src/system-ui/chrome.tsx
@@ -16,10 +16,12 @@
 // build time and template-interpolated fragments are a compile error, so the
 // complete theme-selected classes stay visible to the compiler.
 
+import { lw } from "./words.ts";
+import { getOps } from "@pocketjs/framework";
 import { Image, Text, View } from "@pocketjs/framework/components";
 import { type CaptionState, type DesktopTheme } from "./theme.ts";
 import type { DeskIcon, MenuDef, Popup, TaskEntry, WinCtl } from "./state.ts";
-import { captionSlots, desktopIconPosition } from "./wm.ts";
+import { DESK_ICON_W, DESK_ICON_X_STRIDE, captionSlots, desktopIconPosition } from "./wm.ts";
 
 /** Desktop text. The baked slot rides the style prop — the class table never
  *  sees it (baked per-app via pak.json, docs in gen-assets.ts) — and the
@@ -197,7 +199,7 @@ export function Taskbar(props: {
             theme={props.theme}
             bold
             cls={props.theme.startText}
-            t="Start"
+            t={lw().start}
           />
         </View>
       ) : null}
@@ -552,6 +554,40 @@ export function StartMenu(props: {
   );
 }
 
+/** How far a desktop label wider than its cell moves from the cell's centre,
+ *  so that it stays on the screen: a label is centred under its icon, and one
+ *  wider than the cell (a long name, "マイ コンピュータ") would otherwise run
+ *  past the screen's edge beside the first column. `cellX` is the cell's
+ *  left edge, `width` the label's. */
+export function desktopLabelShift(cellX: number, width: number, viewportW: number): number {
+  if (width <= DESK_ICON_W) return 0;
+  const centred = (DESK_ICON_W - width) / 2;
+  const leftmost = 2 - cellX;
+  const rightmost = viewportW > 0 ? viewportW - 2 - cellX - width : centred;
+  return Math.round(Math.max(leftmost, Math.min(centred, rightmost)) - centred);
+}
+
+/** The widest label a column of icons has room for: a wider one would run
+ *  under the next column's. */
+export const DESK_LABEL_MAX_W = DESK_ICON_X_STRIDE - 2;
+
+/** A desktop label as it is drawn: whole when it fits the column, when it
+ *  is selected or when no icon stands beside it in the next column on
+ *  either side (no label to run under), else cut with "..." to fit, the way
+ *  a desktop shortens a long name until it is selected. */
+export function desktopLabelText(
+  label: string,
+  selected: boolean,
+  measure: (text: string) => number,
+  crowded = true,
+): string {
+  if (selected || !crowded || measure(label) <= DESK_LABEL_MAX_W) return label;
+  const chars = [...label];
+  let n = chars.length;
+  while (n > 1 && measure(`${chars.slice(0, n).join("").trimEnd()}...`) > DESK_LABEL_MAX_W) n--;
+  return `${chars.slice(0, n).join("").trimEnd()}...`;
+}
+
 /** Desktop icons: column-major 32px art + theme-selected labels, anchored
  *  to the theme's screen edge. */
 export function DesktopIcons(props: {
@@ -561,6 +597,18 @@ export function DesktopIcons(props: {
   viewportW: number;
   theme: DesktopTheme;
 }) {
+  const measure = (text: string) => {
+    const ops = getOps();
+    return ops.measureText ? ops.measureText(text, props.theme.fontSlot("ui")) : 0;
+  };
+  // Column-major: the icon beside index i in the next column is i + rows.
+  const crowded = (i: number) => {
+    const rows = Math.max(1, props.rows);
+    return i - rows >= 0 || i + rows < props.icons.length;
+  };
+  const shown = (i: number, label: string) => desktopLabelText(label, props.selected === i, measure, crowded(i));
+  // The label's box: its text and the selection's 2px on each side.
+  const labelW = (label: string) => Math.ceil(measure(label)) + 4;
   return (
     <View class="absolute inset-0">
       {props.icons.map((icon, i) => (
@@ -588,8 +636,15 @@ export function DesktopIcons(props: {
                 ? props.theme.desktopSelection
                 : props.theme.desktopLabelPlain
             }
+            style={{
+              translateX: desktopLabelShift(
+                desktopIconPosition(i, props.rows, props.theme.metrics, props.viewportW).x,
+                labelW(shown(i, icon.label)),
+                props.viewportW,
+              ),
+            }}
           >
-            <UiText theme={props.theme} cls={props.theme.desktopLabel} t={icon.label} />
+            <UiText theme={props.theme} cls={props.theme.desktopLabel} t={shown(i, icon.label)} />
           </View>
         </View>
       ))}
diff --git a/shells/desktop/src/system-ui/pocket-apps.ts b/shells/desktop/src/system-ui/pocket-apps.ts
index 576de9f..02ab26a 100644
--- a/shells/desktop/src/system-ui/pocket-apps.ts
+++ b/shells/desktop/src/system-ui/pocket-apps.ts
@@ -25,25 +25,44 @@ export interface DesktopAbout {
   body: readonly string[];
   /** Shown as text under the body; "" leaves the row out. */
   link: string;
+  /** The body in other languages, by language id ("ja"); a language it
+   *  leaves out shows `body`. */
+  translations: Readonly<Record<string, readonly string[]>>;
 }
 
 /** Read a pocket.about.json value. The System manifest schema has no field
- *  for product copy, so the text lives in this file beside the manifest. Both
+ *  for product copy, so the text lives in this file beside the manifest. All
  *  fields are optional: a missing `body` gives no lines and a missing `link`
- *  no link row. Entries of `body` that are not strings are dropped. */
+ *  no link row. Entries of `body` that are not strings are dropped.
+ *  `translations` holds the body in other languages:
+ *  `{ "ja": { "body": [...] } }`. */
 export function readAbout(value: unknown): DesktopAbout {
   const record =
     value !== null && typeof value === "object"
-      ? (value as { body?: unknown; link?: unknown })
+      ? (value as { body?: unknown; link?: unknown; translations?: unknown })
       : {};
+  const lines = (body: unknown): string[] =>
+    Array.isArray(body) ? body.filter((line): line is string => typeof line === "string") : [];
+  const translations: Record<string, readonly string[]> = {};
+  if (record.translations !== null && typeof record.translations === "object") {
+    for (const [lang, entry] of Object.entries(record.translations as Record<string, unknown>)) {
+      if (entry !== null && typeof entry === "object" && Array.isArray((entry as { body?: unknown }).body)) {
+        translations[lang] = lines((entry as { body: unknown }).body);
+      }
+    }
+  }
   return {
-    body: Array.isArray(record.body)
-      ? record.body.filter((line): line is string => typeof line === "string")
-      : [],
+    body: lines(record.body),
     link: typeof record.link === "string" ? record.link : "",
+    translations,
   };
 }
 
+/** The About body in a language: its translation, else the body as written. */
+export function aboutBody(about: DesktopAbout, lang: string): readonly string[] {
+  return about.translations[lang] ?? about.body;
+}
+
 /** The About text of the product that installs this System UI. This
  *  repository's file describes the shell; a product that bundles the System
  *  UI under its own pocket.system.json puts its own pocket.about.json beside
diff --git a/shells/desktop/src/system-ui/programs.tsx b/shells/desktop/src/system-ui/programs.tsx
index 61799b6..b374483 100644
--- a/shells/desktop/src/system-ui/programs.tsx
+++ b/shells/desktop/src/system-ui/programs.tsx
@@ -7,6 +7,7 @@
 // (cx, cy) from wm.ts hitRegion — origin at the frame's inner top-left,
 // below caption (and menu bar if present).
 
+import { appTitle, lang, lw, themeWord } from "./words.ts";
 import { createMemo } from "solid-js";
 import {
   CompositorSurface,
@@ -22,7 +23,7 @@ import {
   type VSeg,
 } from "./notepad.ts";
 import { MINES_W, type Cell } from "./mines.ts";
-import { DESKTOP_ABOUT, DESKTOP_NAME } from "./pocket-apps.ts";
+import { DESKTOP_ABOUT, DESKTOP_NAME, aboutBody } from "./pocket-apps.ts";
 import {
   PLACES,
   type AboutData,
@@ -119,8 +120,8 @@ export function NotepadView(props: {
   };
   return (
     <View class={props.theme.notepadWell}>
-      {d.layout().status === "companion-required" ? <UiText theme={props.theme} t="Pair a companion to enable text layout." /> : null}
-      {d.layout().status === "error" ? <UiText theme={props.theme} t={d.layout().error ?? "Text layout unavailable"} /> : null}
+      {d.layout().status === "companion-required" ? <UiText theme={props.theme} t={lw().layoutCompanion} /> : null}
+      {d.layout().status === "error" ? <UiText theme={props.theme} t={d.layout().error ?? lw().layoutUnavailable} /> : null}
       <View class="flex-1 relative overflow-hidden">
         <View
           class="absolute left-[3] top-[3] right-0 flex-col"
@@ -192,8 +193,8 @@ export function PocketAppView(props: {
     <View class="flex-1 relative overflow-hidden bg-[#000000]">
       <View class={props.theme.pocketLoading}>
         <Image class="w-[32] h-[32] mb-[8]" src={props.theme.icon("pocket", 32)} />
-        <UiText theme={props.theme} t={`Starting ${props.data.app.title}...`} />
-        <UiText theme={props.theme} cls={props.theme.mutedText} t="Arrow keys + Z/X/A/S + Q/W" />
+        <UiText theme={props.theme} t={lw().starting(appTitle(props.data.app))} />
+        <UiText theme={props.theme} cls={props.theme.mutedText} t={lw().controlsHint} />
       </View>
       <CompositorSurface
         class="absolute inset-0"
@@ -478,6 +479,14 @@ export function folderToolEnabled(d: FolderData, tool: FolderTool): boolean {
   return d.place() !== "computer";
 }
 
+/** A place's name in the active language. */
+function placeName(id: string, label: string): string {
+  if (id === "computer") return lw().myComputer;
+  if (id === "documents") return lw().myDocuments;
+  if (id === "recycle") return lw().recycleBin;
+  return label;
+}
+
 export function FolderView(props: {
   data: FolderData;
   resizable: boolean;
@@ -505,7 +514,7 @@ export function FolderView(props: {
         ))}
         {props.theme.folderAddressLabel !== "" ? (
           <View class="ml-[6] mr-[2]">
-            <UiText theme={props.theme} t={props.theme.folderAddressLabel} />
+            <UiText theme={props.theme} t={themeWord(props.theme.folderAddressLabel)} />
           </View>
         ) : null}
         <View class={props.theme.folderAddress}>
@@ -513,13 +522,13 @@ export function FolderView(props: {
           <UiText
             theme={props.theme}
             cls={props.theme.folderAddressText}
-            t={place().label}
+            t={placeName(place().id, place().label)}
           />
         </View>
         {props.theme.folderSearch !== "" ? (
           <View class={props.theme.folderSearch}>
             <Image class="w-[16] h-[16]" src={props.theme.icon("find", 16)} />
-            <UiText theme={props.theme} cls={props.theme.folderSearchText} t="Search" />
+            <UiText theme={props.theme} cls={props.theme.folderSearchText} t={lw().search} />
           </View>
         ) : null}
       </View>
@@ -534,7 +543,7 @@ export function FolderView(props: {
               theme={props.theme}
               bold
               cls={props.theme.folderSideHeadingText}
-              t={props.theme.folderSideHeadingLabel}
+              t={themeWord(props.theme.folderSideHeadingLabel)}
             />
           </View>
         ) : null}
@@ -546,7 +555,7 @@ export function FolderView(props: {
                 <UiText
                   theme={props.theme}
                   cls={props.theme.folderSideText(current(i), props.active)}
-                  t={place.label}
+                  t={placeName(place.id, place.label)}
                 />
               </View>
             </View>
@@ -556,13 +565,13 @@ export function FolderView(props: {
       <View class={props.theme.folderWell}>
         <View class="h-[17] flex-row shrink-0">
           <View class={props.theme.folderHeader("name")}>
-            <UiText theme={props.theme} t="Name" />
+            <UiText theme={props.theme} t={lw().name} />
           </View>
           <View class={props.theme.folderHeader("size")}>
-            <UiText theme={props.theme} t="Size" />
+            <UiText theme={props.theme} t={lw().size} />
           </View>
           <View class={props.theme.folderHeader("type")}>
-            <UiText theme={props.theme} t="Type" />
+            <UiText theme={props.theme} t={lw().type} />
           </View>
         </View>
         {d.rows().map((row, i) => (
@@ -607,7 +616,7 @@ export function FolderView(props: {
         ))}
         {d.rows().length === 0 ? (
           <View class="flex-1 flex-col justify-center items-center">
-            <UiText theme={props.theme} cls={props.theme.mutedText} t="(empty)" />
+            <UiText theme={props.theme} cls={props.theme.mutedText} t={lw().empty} />
           </View>
         ) : null}
       </View>
@@ -680,7 +689,7 @@ export function AboutView(props: {
         <View class={props.theme.popupSeparatorDark} />
         <View class={props.theme.popupSeparatorLight} />
       </View>
-      {DESKTOP_ABOUT.body.map((line) => (
+      {aboutBody(DESKTOP_ABOUT, lang()).map((line) => (
         <UiText theme={props.theme} t={line} />
       ))}
       {DESKTOP_ABOUT.link !== "" ? (
@@ -693,7 +702,7 @@ export function AboutView(props: {
       <View class="flex-1" />
       <View class="flex-row justify-end">
         <DialogButton
-          label="OK"
+          label={lw().ok}
           armed={props.data.armed() === "ok"}
           primary
           theme={props.theme}
@@ -747,24 +756,24 @@ export function ShutdownView(props: {
       <View class="flex-row items-start gap-[10]">
         <Image class="w-[32] h-[32]" src={props.theme.icon("shutdown", 32)} />
         <View class="flex-col gap-[2]">
-          <UiText theme={props.theme} t="What do you want the computer to do?" />
+          <UiText theme={props.theme} t={lw().shutDownAsk} />
         </View>
       </View>
       <View class="h-[10]" />
       <View class="flex-col pl-[46]">
-        {radio(0, "Shut down")}
-        {radio(1, "Restart")}
+        {radio(0, lw().shutDownChoice)}
+        {radio(1, lw().restart)}
       </View>
       <View class="flex-1" />
       <View class="flex-row justify-end gap-[6]">
         <DialogButton
-          label="OK"
+          label={lw().ok}
           armed={props.data.armed() === "ok"}
           primary
           theme={props.theme}
         />
         <DialogButton
-          label="Cancel"
+          label={lw().cancel}
           armed={props.data.armed() === "cancel"}
           theme={props.theme}
         />
diff --git a/shells/desktop/src/system-ui/svc.ts b/shells/desktop/src/system-ui/svc.ts
index c9bc78b..555661a 100644
--- a/shells/desktop/src/system-ui/svc.ts
+++ b/shells/desktop/src/system-ui/svc.ts
@@ -23,6 +23,11 @@
 //   {t:"theme", id}            select the theme with that id ("classic",
 //                              "xp" or "aqua"). An id that names no theme
 //                              is ignored
+//   {t:"lang", id, titles}     the language the shell draws in ("en" or
+//                              "ja", words.ts), and the installed apps'
+//                              titles in it by package id (optional; an app
+//                              it leaves out keeps its manifest's title). An
+//                              id with no catalog is ignored
 //
 // guest → host intents:
 //   {t:"theme", id}            the active theme: sent once after boot and
@@ -50,7 +55,8 @@ export interface HostEvent {
     | "paste"
     | "ime"
     | "open"
-    | "theme";
+    | "theme"
+    | "lang";
   w?: number;
   h?: number;
   epoch?: number;
@@ -73,8 +79,10 @@ export interface HostEvent {
   c?: number | null;
   /** Package id of the installed app an "open" line names. */
   package?: string;
-  /** Theme id a "theme" line selects. */
+  /** Theme id a "theme" line selects, or the language a "lang" line names. */
   id?: string;
+  /** A "lang" line's app titles in that language, by package id. */
+  titles?: Record<string, string>;
 }
 
 export type CursorKind =
diff --git a/shells/desktop/src/system-ui/words.ts b/shells/desktop/src/system-ui/words.ts
new file mode 100644
index 0000000..3669c4f
--- /dev/null
+++ b/shells/desktop/src/system-ui/words.ts
@@ -0,0 +1,228 @@
+// SPDX-License-Identifier: GPL-3.0-only
+// src/system-ui/words.ts — the System UI's words in English and Japanese.
+//
+// The host names the language on the svc "lang" line (svc.ts), with the
+// titles of its installed apps in that language when it has them; the
+// shell draws every label it owns from the active catalog through `lw()`, so
+// the Start menu, the desktop icons, the menus and the dialogs follow a
+// switch. Without a lang line the shell is English. File names (README.TXT,
+// Program Files) and shortcut names (Cmd+W) are the same in every language.
+//
+// Japanese follows the names Japanese desktop systems of the period used
+// (マイ コンピュータ, ごみ箱, 右端で折り返す), in です・ます where a sentence
+// is a sentence.
+
+import { createSignal } from "solid-js";
+
+export type Lang = "en" | "ja";
+
+const EN = {
+  start: "Start",
+  myComputer: "My Computer",
+  myDocuments: "My Documents",
+  recycleBin: "Recycle Bin",
+  notepad: "Notepad",
+  minesweeper: "Minesweeper",
+  /** The program name Aqua's screen bar shows for a folder window. */
+  files: "Files",
+  untitled: "Untitled",
+  /** A Notepad window's title: the document's name, then the program's. */
+  notepadTitle: (name: string) => `${name} - Notepad`,
+  about: (name: string) => `About ${name}`,
+  programs: "Programs",
+  allPrograms: "All Programs",
+  documents: "Documents",
+  settings: "Settings",
+  find: "Find",
+  help: "Help",
+  run: "Run...",
+  shutDownMenu: "Shut Down...",
+  turnOff: "Turn Off Computer",
+  // menus
+  file: "File",
+  edit: "Edit",
+  game: "Game",
+  new: "New",
+  exit: "Exit",
+  undo: "Undo",
+  redo: "Redo",
+  cut: "Cut",
+  copy: "Copy",
+  paste: "Paste",
+  selectAll: "Select All",
+  timeDate: "Time/Date",
+  wordWrap: "Word Wrap",
+  minimize: "Minimize",
+  maximize: "Maximize",
+  restore: "Restore",
+  close: "Close",
+  arrangeIcons: "Arrange Icons",
+  refresh: "Refresh",
+  newTextDocument: "New Text Document",
+  properties: "Properties",
+  // folders
+  search: "Search",
+  address: "Address",
+  folders: "Folders",
+  otherPlaces: "Other Places",
+  name: "Name",
+  size: "Size",
+  type: "Type",
+  empty: "(empty)",
+  controlPanel: "Control Panel",
+  printers: "Printers",
+  localDisk: "Local Disk",
+  cdromDisc: "CD-ROM Disc",
+  systemFolder: "System Folder",
+  fileFolder: "File Folder",
+  batchFile: "Batch File",
+  systemFile: "System file",
+  textDocument: "Text Document",
+  // dialogs
+  shutDown: "Shut Down",
+  shutDownAsk: "What do you want the computer to do?",
+  shutDownChoice: "Shut down",
+  restart: "Restart",
+  ok: "OK",
+  cancel: "Cancel",
+  // Pocket apps and Notepad's layout
+  starting: (title: string) => `Starting ${title}...`,
+  controlsHint: "Arrow keys + Z/X/A/S + Q/W",
+  layoutUnavailable: "Text layout unavailable",
+  layoutCompanion: "Pair a companion to enable text layout.",
+} as const;
+
+type Catalog = {
+  [K in keyof typeof EN]: (typeof EN)[K] extends (...args: infer A) => string ? (...args: A) => string : string;
+};
+
+/** `text` and the half-width space Japanese puts after a Latin word or a number. */
+const spaced = (text: string) => (/[A-Za-z0-9.)]$/.test(text) ? `${text} ` : text);
+
+const JA: Catalog = {
+  start: "スタート",
+  myComputer: "マイ コンピュータ",
+  myDocuments: "マイ ドキュメント",
+  recycleBin: "ごみ箱",
+  notepad: "メモ帳",
+  minesweeper: "マインスイーパ",
+  files: "ファイル",
+  untitled: "無題",
+  notepadTitle: (name) => `${name} - メモ帳`,
+  about: (name) => `${spaced(name)}について`,
+  programs: "プログラム",
+  allPrograms: "すべてのプログラム",
+  documents: "書類",
+  settings: "設定",
+  find: "検索",
+  help: "ヘルプ",
+  run: "実行...",
+  shutDownMenu: "シャットダウン...",
+  turnOff: "電源を切る",
+  file: "ファイル",
+  edit: "編集",
+  game: "ゲーム",
+  new: "新規",
+  exit: "終了",
+  undo: "元に戻す",
+  redo: "やり直し",
+  cut: "切り取り",
+  copy: "コピー",
+  paste: "貼り付け",
+  selectAll: "すべて選択",
+  timeDate: "日付と時刻",
+  wordWrap: "右端で折り返す",
+  minimize: "最小化",
+  maximize: "最大化",
+  restore: "元のサイズに戻す",
+  close: "閉じる",
+  arrangeIcons: "アイコンの整列",
+  refresh: "最新の情報に更新",
+  newTextDocument: "新規テキスト ドキュメント",
+  properties: "プロパティ",
+  search: "検索",
+  address: "アドレス",
+  folders: "フォルダ",
+  otherPlaces: "その他",
+  name: "名前",
+  size: "サイズ",
+  type: "種類",
+  empty: "(空)",
+  controlPanel: "コントロール パネル",
+  printers: "プリンタ",
+  localDisk: "ローカル ディスク",
+  cdromDisc: "CD-ROM ディスク",
+  systemFolder: "システム フォルダ",
+  fileFolder: "ファイル フォルダ",
+  batchFile: "バッチ ファイル",
+  systemFile: "システム ファイル",
+  textDocument: "テキスト ドキュメント",
+  shutDown: "シャットダウン",
+  shutDownAsk: "コンピュータをどうしますか?",
+  shutDownChoice: "シャットダウン",
+  restart: "再起動",
+  ok: "OK",
+  cancel: "キャンセル",
+  starting: (title) => `${spaced(title)}を起動しています...`,
+  controlsHint: "方向キー + Z/X/A/S + Q/W",
+  layoutUnavailable: "テキストのレイアウトを使えません",
+  layoutCompanion: "テキストのレイアウトには、コンパニオンとの接続が必要です。",
+};
+
+const CATALOGS: Record<Lang, Catalog> = { en: EN as unknown as Catalog, ja: JA };
+
+const [active, setActive] = createSignal<Lang>("en");
+const [titles, setTitles] = createSignal<Readonly<Record<string, string>>>({});
+
+/** The active language. */
+export const lang = active;
+
+/** The active catalog. Read it where a label is computed, so a switch redraws it. */
+export const lw = (): Catalog => CATALOGS[active()];
+
+/** The catalog of a language, for code that is not reactive (tests, one-off titles). */
+export const wordsIn = (language: Lang): Catalog => CATALOGS[language];
+
+/** A value a lang line names, or null when this shell has no catalog for it. */
+export function langOf(value: unknown): Lang | null {
+  return value === "en" || value === "ja" ? value : null;
+}
+
+/**
+ * Follow a lang line: its language and its apps' titles by package id. A line
+ * naming a language the shell has no catalog for changes nothing. Returns
+ * true when anything changed.
+ */
+export function applyLang(id: unknown, appTitles?: unknown): boolean {
+  const next = langOf(id);
+  if (!next) return false;
+  const named: Record<string, string> = {};
+  if (appTitles && typeof appTitles === "object") {
+    for (const [pkg, title] of Object.entries(appTitles as Record<string, unknown>)) {
+      if (typeof title === "string" && title !== "") named[pkg] = title;
+    }
+  }
+  const same = next === active() && JSON.stringify(named) === JSON.stringify(titles());
+  if (same) return false;
+  setActive(next);
+  setTitles(named);
+  return true;
+}
+
+/** Labels the themes carry as data (theme.ts), by their English text. */
+const THEME_WORDS: Record<string, keyof Catalog> = {
+  Address: "address",
+  Folders: "folders",
+  "Other Places": "otherPlaces",
+};
+
+/** A label a theme carries, in the active language; text this catalog does not know stays as it is. */
+export function themeWord(text: string): string {
+  const key = THEME_WORDS[text];
+  return key ? (lw()[key] as string) : text;
+}
+
+/** An installed app's title in the active language: the host's, else the manifest's. */
+export function appTitle(app: { package: string; title: string }): string {
+  return titles()[app.package] ?? app.title;
+}
diff --git a/shells/desktop/test/system-ui.test.ts b/shells/desktop/test/system-ui.test.ts
index 69e8976..69437ab 100644
--- a/shells/desktop/test/system-ui.test.ts
+++ b/shells/desktop/test/system-ui.test.ts
@@ -82,11 +82,14 @@ import {
   DESKTOP_NAME,
   POCKET_APPS,
   WINDOW_TITLE_PREFIX,
+  aboutBody,
   appWindowTitle,
   pocketAppByPackage,
   readAbout,
   readWindowTitlePrefix,
 } from "../src/system-ui/pocket-apps.ts";
+import { appTitle, applyLang, lw, themeWord, wordsIn } from "../src/system-ui/words.ts";
+import { DESK_LABEL_MAX_W, desktopLabelShift, desktopLabelText } from "../src/system-ui/chrome.tsx";
 import about from "../pocket.about.json";
 import system from "../pocket.system.json";
 import {
@@ -161,7 +164,7 @@ describe("Pocket app desktop catalog", () => {
   });
 
   test("the About dialog takes its text from pocket.about.json", () => {
-    expect(DESKTOP_ABOUT).toEqual(about);
+    expect(DESKTOP_ABOUT).toEqual({ ...about, translations: {} });
     // This repository's file describes the shell.
     expect(DESKTOP_ABOUT).toEqual({
       body: [
@@ -171,6 +174,7 @@ describe("Pocket app desktop catalog", () => {
         "live in the guest.",
       ],
       link: "github.com/pocket-nexus/pocket-shell",
+      translations: {},
     });
   });
 
@@ -212,31 +216,88 @@ describe("Pocket app desktop catalog", () => {
         link: "example.org",
         windowTitlePrefix: "Desk",
       }),
-    ).toEqual({ body: ["One line."], link: "example.org" });
+    ).toEqual({ body: ["One line."], link: "example.org", translations: {} });
   });
 
   test("an About file may leave out its body, its link or both", () => {
     expect(readAbout({ body: ["One line."], link: "example.org" })).toEqual({
       body: ["One line."],
       link: "example.org",
+      translations: {},
     });
     expect(readAbout({ body: ["One line."] })).toEqual({
       body: ["One line."],
       link: "",
+      translations: {},
     });
     expect(readAbout({ link: "example.org" })).toEqual({
       body: [],
       link: "example.org",
+      translations: {},
     });
     // Entries that are not strings are dropped; a body or link of another
     // type reads as absent.
     expect(readAbout({ body: ["a", 1, null, "b"], link: 2 })).toEqual({
       body: ["a", "b"],
       link: "",
+      translations: {},
     });
-    expect(readAbout({ body: "One line." })).toEqual({ body: [], link: "" });
+    expect(readAbout({ body: "One line." })).toEqual({ body: [], link: "", translations: {} });
     for (const value of [{}, [], null, undefined, "text", 3])
-      expect(readAbout(value)).toEqual({ body: [], link: "" });
+      expect(readAbout(value)).toEqual({ body: [], link: "", translations: {} });
+  });
+
+  test("an About file may carry its body in other languages", () => {
+    const read = readAbout({
+      body: ["One line."],
+      translations: { ja: { body: ["一行。", 2] }, fr: "texte", de: { link: "x" } },
+    });
+    expect(read.translations).toEqual({ ja: ["一行。"] });
+    expect(aboutBody(read, "ja")).toEqual(["一行。"]);
+    // A language the file does not carry shows the body as written.
+    expect(aboutBody(read, "en")).toEqual(["One line."]);
+    expect(aboutBody(read, "fr")).toEqual(["One line."]);
+  });
+
+  test("the shell's words: one key set in each language, and the lang line", () => {
+    expect(Object.keys(wordsIn("ja")).sort()).toEqual(Object.keys(wordsIn("en")).sort());
+    for (const [key, value] of Object.entries(wordsIn("ja"))) {
+      if (typeof value === "string") expect([key, value.length > 0]).toEqual([key, true]);
+    }
+    expect(wordsIn("ja").notepadTitle("README.TXT")).toBe("README.TXT - メモ帳");
+    expect(wordsIn("ja").about("Pocket Nexus")).toBe("Pocket Nexus について");
+    expect(wordsIn("en").about("Pocket Nexus")).toBe("About Pocket Nexus");
+
+    expect(lw().start).toBe("Start");
+    expect(applyLang("de")).toBe(false);
+    expect(applyLang("ja", { "dev.pocket-nexus.hero": "ヒーロー", other: 3 })).toBe(true);
+    expect(lw().start).toBe("スタート");
+    expect(appTitle({ package: "dev.pocket-nexus.hero", title: "Hero" })).toBe("ヒーロー");
+    expect(appTitle({ package: "dev.pocket-nexus.other", title: "Other" })).toBe("Other");
+    expect(themeWord("Address")).toBe("アドレス");
+    expect(themeWord("Classic 98")).toBe("Classic 98");
+    // The same line again changes nothing; English gives the manifest titles back.
+    expect(applyLang("ja", { "dev.pocket-nexus.hero": "ヒーロー" })).toBe(false);
+    expect(applyLang("en")).toBe(true);
+    expect(appTitle({ package: "dev.pocket-nexus.hero", title: "Hero" })).toBe("Hero");
+  });
+
+  test("a desktop label wider than its column is cut until it is selected, and stays on the screen", () => {
+    const measure = (text: string) => [...text].length * 11;
+    expect(desktopLabelText("ごみ箱", false, measure)).toBe("ごみ箱");
+    const cut = desktopLabelText("インストールガイド", false, measure);
+    expect(cut.endsWith("...")).toBe(true);
+    expect(measure(cut)).toBeLessThanOrEqual(DESK_LABEL_MAX_W);
+    expect(desktopLabelText("インストールガイド", true, measure)).toBe("インストールガイド");
+    // With no icon beside it in the next column: the whole name, moved onto the screen.
+    expect(desktopLabelText("インストールガイド", false, measure, false)).toBe("インストールガイド");
+    // A label as wide as its cell or narrower stays centred.
+    expect(desktopLabelShift(8, 74, 800)).toBe(0);
+    // A wide label beside the left edge moves right until it starts 2px in.
+    expect(8 + (74 - 100) / 2 + desktopLabelShift(8, 100, 800)).toBe(2);
+    // Beside the right edge it moves left until it ends 2px in.
+    const x = 800 - 8 - 74;
+    expect(x + (74 - 100) / 2 + desktopLabelShift(x, 100, 800) + 100).toBe(798);
   });
 
   test("a host open line resolves installed apps only", () => {