fix(desktop): quiet gate for workspace switches instead of boot splash

desktop/src/app/App.tsx

@@ -7,6 +7,7 @@ import {
   useCallback,
   useEffect,
   useLayoutEffect,
+  useRef,
   useState,
 } from "react";
 
@@ -26,6 +27,7 @@ import { isSharedIdentity as isSharedIdentityCmd } from "@/shared/api/tauri";
 import { listenForDeepLinks } from "@/shared/deep-link";
 import { useSystemColorScheme } from "@/shared/theme/useSystemColorScheme";
 import { Button } from "@/shared/ui/button";
+import { Spinner } from "@/shared/ui/spinner";
 import { StartupWindowDragRegion } from "@/shared/ui/StartupWindowDragRegion";
 import { StepProgress } from "@/shared/ui/step-progress";
 
@@ -54,6 +56,31 @@ function AppLoadingGate() {
   );
 }
 
+// Quiet gate for switching between already-set-up workspaces: visually empty
+// unless the switch takes long, so fast switches don't flash the boot splash.
+function WorkspaceSwitchGate() {
+  const [showSpinner, setShowSpinner] = useState(false);
+
+  useEffect(() => {
+    const timer = window.setTimeout(() => setShowSpinner(true), 300);
+    return () => window.clearTimeout(timer);
+  }, []);
+
+  return (
+    <div
+      className="flex min-h-dvh items-center justify-center bg-background"
+      data-testid="workspace-switch-gate"
+      role="status"
+    >
+      <StartupWindowDragRegion />
+      <span className="sr-only">Switching workspace…</span>
+      {showSpinner ? (
+        <Spinner aria-hidden="true" className="text-muted-foreground" />
+      ) : null}
+    </div>
+  );
+}
+
 function OnboardingLoadingGate() {
   const systemColorScheme = useSystemColorScheme();
 
@@ -155,12 +182,14 @@ function AppReady({
   canBackToWorkspaceSetup,
   isCompletingFirstRunWorkspace,
   isSharedIdentity,
+  isWorkspaceSwitch,
   onFirstRunWorkspaceSettled,
   onBackToWorkspaceSetup,
 }: {
   canBackToWorkspaceSetup: boolean;
   isCompletingFirstRunWorkspace: boolean;
   isSharedIdentity: boolean;
+  isWorkspaceSwitch: boolean;
   onFirstRunWorkspaceSettled: () => void;
   onBackToWorkspaceSetup: () => void;
 }) {
@@ -193,7 +222,7 @@ function AppReady({
       return <OnboardingLoadingGate />;
     }
 
-    return <AppLoadingGate />;
+    return isWorkspaceSwitch ? <WorkspaceSwitchGate /> : <AppLoadingGate />;
   }
 
   return <RouterProvider router={router} />;
@@ -251,6 +280,17 @@ export function App() {
   // Composite key: changes when workspace ID changes OR when
   // the active workspace's config is updated (relayUrl/token).
   const workspaceKey = `${activeWorkspace?.id ?? "none"}-${reinitKey}`;
+
+  // Latch once the workspace key deviates from its cold-boot value: from then
+  // on, loading phases are in-app switches and get the quiet gate instead of
+  // the full "Setting up your workspace" splash.
+  const initialWorkspaceKeyRef = useRef(workspaceKey);
+  const hasSwitchedWorkspaceRef = useRef(false);
+  if (workspaceKey !== initialWorkspaceKeyRef.current) {
+    hasSwitchedWorkspaceRef.current = true;
+  }
+  const isWorkspaceSwitch = hasSwitchedWorkspaceRef.current;
+
   const workspace = useWorkspaceInit(
     activeWorkspace,
     workspaceKey,
@@ -306,14 +346,15 @@ export function App() {
       return <OnboardingLoadingGate />;
     }
 
-    return <AppLoadingGate />;
+    return isWorkspaceSwitch ? <WorkspaceSwitchGate /> : <AppLoadingGate />;
   }
 
   return (
     <WorkspaceQueryProvider key={workspaceKey}>
       <AppReady
         canBackToWorkspaceSetup={canBackToWorkspaceSetup}
         isCompletingFirstRunWorkspace={isCompletingFirstRunWorkspace}
+        isWorkspaceSwitch={isWorkspaceSwitch}
         key={workspaceKey}
         isSharedIdentity={sharedIdentity}
         onFirstRunWorkspaceSettled={handleFirstRunWorkspaceSettled}

desktop/src/testing/e2eBridge.ts

@@ -89,6 +89,9 @@ type E2eConfig = {
     channelsReadError?: string;
     feedReadError?: string;
     canvasReadError?: string;
+    /** Delay (ms) for `apply_workspace` so e2e tests can observe the
+     *  workspace-switch gate. 0/undefined = instant. */
+    applyWorkspaceDelayMs?: number;
     openDmDelayMs?: number;
     sendMessageDelayMs?: number;
     usersBatchDelayMs?: number;
@@ -7130,8 +7133,15 @@ export function maybeInstallE2eTauriMocks() {
         return importMockIdentity(
           (payload as { nsec?: string } | null)?.nsec ?? "",
         );
-      case "apply_workspace":
+      case "apply_workspace": {
+        const applyDelayMs = activeConfig?.mock?.applyWorkspaceDelayMs ?? 0;
+        if (applyDelayMs > 0) {
+          return new Promise((resolve) =>
+            window.setTimeout(resolve, applyDelayMs),
+          );
+        }
         return;
+      }
       case "get_profile":
         return handleGetProfile(activeConfig);
       case "update_profile":

desktop/tests/e2e/workspace-rail.spec.ts

@@ -73,6 +73,34 @@ test.describe("workspace rail", () => {
       .toBe(WORKSPACE_B.id);
   });
 
+  test("shows the quiet switch gate, not the boot splash, while switching", async ({
+    page,
+  }) => {
+    // Slow down apply_workspace so the loading phase is observable.
+    await installMockBridge(
+      page,
+      { applyWorkspaceDelayMs: 800 },
+      { skipWorkspaceSeed: true },
+    );
+    await seedWorkspaces(page, [WORKSPACE_A, WORKSPACE_B], WORKSPACE_A.id);
+    await page.goto("/");
+
+    // Cold boot still uses the full splash.
+    await expect(page.getByTestId("app-loading-gate")).toBeVisible();
+    const buttonB = page.getByTestId(`workspace-rail-button-${WORKSPACE_B.id}`);
+    await expect(buttonB).toBeVisible();
+
+    await buttonB.click();
+
+    // The switch renders the quiet gate; the "Setting up your workspace"
+    // splash must not reappear.
+    await expect(page.getByTestId("workspace-switch-gate")).toBeVisible();
+    await expect(page.getByTestId("app-loading-gate")).toHaveCount(0);
+
+    // The app settles into the new workspace once apply completes.
+    await expect(buttonB).toHaveAttribute("aria-current", "true");
+  });
+
   test("hides the rail with a single workspace", async ({ page }) => {
     await installMockBridge(page, undefined, { skipWorkspaceSeed: true });
     await seedWorkspaces(page, [WORKSPACE_A], WORKSPACE_A.id);

desktop/tests/helpers/bridge.ts

@@ -111,6 +111,8 @@ type MockBridgeOptions = {
   channelsReadError?: string;
   feedReadError?: string;
   canvasReadError?: string;
+  /** Delay (ms) for `apply_workspace`; see e2eBridge mock config. */
+  applyWorkspaceDelayMs?: number;
   openDmDelayMs?: number;
   sendMessageDelayMs?: number;
   usersBatchDelayMs?: number;