FN-7980: dismiss mobile task popups on swipe/back without leaving board

Register mobile task popups on the Fusion nav stack so browser Back, iOS edge-swipe, and Android Back close the popup and keep the board/list visible.

- Push a modal nav entry when opening a mobile task popup and clean it up on close
- Route FloatingWindow and shortcut closes through nav-aware popup close
- Add swipe-back tests for board and list popup dismissal
- Document popup Back behavior in the dashboard guide

Files changed:
 docs/dashboard-guide.md                            |  3 +-
 packages/dashboard/app/App.tsx                     | 35 +++++++--
 .../__tests__/TaskDetail.swipe-back.test.tsx       | 84 +++++++++++++++++++++-
 3 files changed, 114 insertions(+), 8 deletions(-)

Fusion-Task-Id: FN-7980

Fusion-Task-Lineage: e321a1df-e271-41c0-81af-3560d759f7bb

Co-authored-by: Fusion (runfusion.ai) <noreply@runfusion.ai>

docs/dashboard-guide.md

@@ -68,7 +68,8 @@ The installed mobile/PWA home-screen icons are generated from `packages/dashboar
 
 The dashboard now handles browser back navigation consistently on desktop and mobile.
 Using Back will first dismiss open modals and then step back through in-app view changes before leaving the app.
-When task detail is open from a board card, mobile list row, right-dock/activity/onboarding link, deep link, or another task detail link, one browser/Android Back action closes the current detail first and restores the prior dashboard context (for example, nested task detail → previous task detail, or task detail → board).
+When task detail is open from a board card, task popup, mobile list row, right-dock/activity/onboarding link, deep link, or another task detail link, one browser, iOS edge-swipe, or Android Back action closes the current detail first and restores the prior dashboard context (for example, nested task detail → previous task detail, or task detail → board/list).
+<!-- FNXC:TaskDetailSwipeBackDocs 2026-07-15-10:36: Mobile task popups now register the same navigation entry as modal and full-panel task detail, so every Back delivery mechanism dismisses the popup before it can leave the originating Board or List. -->
 On mobile board-card detail, **Back to board** also restores the prior board/card scroll position so the same lane context remains visible.
 <!-- FNXC:BoardNavigationDocs 2026-06-29-20:45: Mobile full-panel task detail temporarily replaces the board, so the user-facing navigation guide must document that Back to board restores the board/card scroll context instead of returning to the top of the board. -->
 This behavior used to be mobile-only, and now applies across all viewports.

packages/dashboard/app/App.tsx

@@ -474,9 +474,36 @@ function AppInner() {
   Open popped-out task-detail windows. Each entry is a task snapshot rendered inside its own movable, resizable, non-blocking FloatingWindow. Several can be open at once and coexist with the right-dock pop-out and terminal (all click-through overlays). Snapshots survive a tasks revalidation; rendering prefers the live row by id and falls back to the snapshot. Pop-out dedupes by task id — re-popping an already-open task is a no-op (its window stays; focus-to-front in FloatingWindow handles re-raising on click).
   */
   const { entries: poppedOutTaskEntries, popOut: popOutTaskDetail, close: closePoppedOutTask } = usePoppedOutTasks();
+  const popupNavCloseRef = useRef(new Map<string, () => void>());
+
+  /*
+  FNXC:TaskDetailSwipeBack 2026-07-15-10:32:
+  Mobile task popups keep Board or List visible, but they are still task-detail
+  surfaces. Give each newly opened popup its own navigation callback so browser,
+  iOS swipe, and Android Back dismiss only that popup rather than leaving the
+  Fusion stack empty and allowing Back to skip past the originating task view.
+  */
+  const closePoppedOutTaskWithNav = useCallback((taskId: string) => {
+    const closeFromHistory = popupNavCloseRef.current.get(taskId);
+    if (closeFromHistory) {
+      popupNavCloseRef.current.delete(taskId);
+      removeNav(closeFromHistory);
+    }
+    closePoppedOutTask(taskId);
+  }, [closePoppedOutTask, removeNav]);
+
   const popOutTaskDetailForCurrentView = useCallback((task: Task | TaskDetail) => {
+    const alreadyOpen = poppedOutTaskEntries.some((entry) => entry.task.id === task.id);
+    if (isMobile && !alreadyOpen) {
+      const closeFromHistory = () => {
+        popupNavCloseRef.current.delete(task.id);
+        closePoppedOutTask(task.id);
+      };
+      popupNavCloseRef.current.set(task.id, closeFromHistory);
+      pushNav({ type: "modal", close: closeFromHistory });
+    }
     popOutTaskDetail(task, taskView);
-  }, [popOutTaskDetail, taskView]);
+  }, [isMobile, poppedOutTaskEntries, popOutTaskDetail, pushNav, closePoppedOutTask, taskView]);
 
   const boardSourceTasks = isRemote && remoteData.tasks.length > 0 ? remoteData.tasks : tasks;
   const [graphWorkflowSelection, setGraphWorkflowSelection] = useState<GraphWorkflowSelection | null>(null);
@@ -1079,12 +1106,12 @@ function AppInner() {
         ],
       },
       {
-        closePoppedOutTask,
+        closePoppedOutTask: closePoppedOutTaskWithNav,
         closeQuickChat: () => setQuickChatOpen(false),
         closeTerminal: closeTerminalWithNav,
       },
     );
-  }, [closePoppedOutTask, closeTerminalWithNav, modalManager, quickChatOpen, visiblePoppedOutTasks]);
+  }, [closePoppedOutTaskWithNav, closeTerminalWithNav, modalManager, quickChatOpen, visiblePoppedOutTasks]);
 
   const openFilesWithNav = useCallback((workspace?: string, initialFile?: string | null) => {
     modalManager.openFiles(workspace, initialFile);
@@ -1812,7 +1839,7 @@ function AppInner() {
       */}
       {visiblePoppedOutTaskEntries.map(({ task: snapshot }) => {
         const liveTask = tasks.find((candidate) => candidate.id === snapshot.id) ?? snapshot;
-        const close = () => closePoppedOutTask(snapshot.id);
+        const close = () => closePoppedOutTaskWithNav(snapshot.id);
         return (
           <FloatingWindow
             key={snapshot.id}

packages/dashboard/app/components/__tests__/TaskDetail.swipe-back.test.tsx

@@ -21,6 +21,7 @@ import type { ProjectInfo } from "../../api";
 import { scopedKey } from "../../utils/projectStorage";
 
 const DEFAULT_PROJECT_ID = "proj-1";
+let mobileTaskPopupEnabled = false;
 
 const defaultSettings: Settings = {
   maxConcurrent: 2,
@@ -45,7 +46,7 @@ vi.mock("../../api", async (importOriginal) => {
   return createDashboardApiMock(() => importOriginal<typeof import("../../api")>(), {
     fetchTasks: vi.fn(() => Promise.resolve([])),
     fetchConfig: vi.fn(() => Promise.resolve({ maxConcurrent: 2, rootDir: "/workspace/project" })),
-    fetchSettings: vi.fn(() => Promise.resolve({ ...defaultSettings })),
+    fetchSettings: vi.fn(() => Promise.resolve({ ...defaultSettings, openMobileTasksInPopup: mobileTaskPopupEnabled })),
     updateSettings: vi.fn(() => Promise.resolve({ ...defaultSettings })),
     fetchGlobalSettings: vi.fn(() => Promise.resolve({})),
     fetchAuthStatus: vi.fn(() => Promise.resolve({ providers: [] })),
@@ -151,7 +152,17 @@ vi.mock("../../components/Board", () => ({
 }));
 
 vi.mock("../../components/ListView", () => ({
-  ListView: ({ tasks, onOpenDetail }: { tasks: Task[]; onOpenDetail: (task: Task, options?: { origin?: "list-mobile" }) => void }) => (
+  ListView: ({
+    tasks,
+    onOpenDetail,
+    onPopOut,
+    openMobileTasksInPopup,
+  }: {
+    tasks: Task[];
+    onOpenDetail: (task: Task, options?: { origin?: "list-mobile" }) => void;
+    onPopOut?: (task: Task) => void;
+    openMobileTasksInPopup?: boolean;
+  }) => (
     <div data-testid="list-view">
       {tasks.map((task) => (
         <button
@@ -159,7 +170,9 @@ vi.mock("../../components/ListView", () => ({
           type="button"
           data-testid={`list-open-${task.id}`}
           onClick={() => {
-            if (mockUseViewportMode() === "mobile") {
+            if (openMobileTasksInPopup && onPopOut) {
+              onPopOut(task);
+            } else if (mockUseViewportMode() === "mobile") {
               onOpenDetail(task, { origin: "list-mobile" });
             }
           }}
@@ -370,6 +383,7 @@ describe("Task detail mobile swipe-back", () => {
       refreshTasks: vi.fn(),
     }));
     mockUseViewportMode.mockReturnValue("mobile");
+    mobileTaskPopupEnabled = false;
     mockUseMobileKeyboard.mockReturnValue({
       keyboardOverlap: 0, viewportHeight: null, viewportOffsetTop: 0, keyboardOpen: false,
     });
@@ -529,6 +543,70 @@ describe("Task detail mobile swipe-back", () => {
     });
   });
 
+  it("dismisses a mobile board task popup on browser popstate while keeping the board visible", async () => {
+    mobileTaskPopupEnabled = true;
+    const task = makeTask("FN-1", "Popup Board Detail");
+    mockUseTasks.mockImplementation(() => ({
+      tasks: [task],
+      createTask: mockCreateTask,
+      moveTask: vi.fn(),
+      deleteTask: vi.fn(),
+      mergeTask: vi.fn(),
+      retryTask: vi.fn(),
+      updateTask: vi.fn(),
+      duplicateTask: vi.fn(),
+      archiveTask: vi.fn(),
+      unarchiveTask: vi.fn(),
+      archiveAllDone: vi.fn(),
+      refreshTasks: vi.fn(),
+    }));
+
+    await renderAppAndWait("board-view");
+    fireEvent.click(screen.getByTestId("open-task-FN-1"));
+
+    await waitFor(() => {
+      expect(screen.getByRole("heading", { name: "Popup Board Detail" })).toBeInTheDocument();
+      expect(screen.getByTestId("board-view")).toBeInTheDocument();
+    });
+
+    dispatchPopState({ navIndex: 0 });
+
+    await waitFor(() => {
+      expect(screen.queryByRole("heading", { name: "Popup Board Detail" })).toBeNull();
+      expect(screen.getByTestId("board-view")).toBeInTheDocument();
+    });
+    expect(dispatchNativeAndroidBack()).toBe(false);
+  });
+
+  it("dismisses a mobile list task popup on native Android Back while keeping the list visible", async () => {
+    mobileTaskPopupEnabled = true;
+    const task = makeTask("FN-1", "Popup List Detail");
+    mockUseTasks.mockImplementation(() => ({
+      tasks: [task],
+      createTask: mockCreateTask,
+      moveTask: vi.fn(), deleteTask: vi.fn(), mergeTask: vi.fn(), retryTask: vi.fn(),
+      updateTask: vi.fn(), duplicateTask: vi.fn(), archiveTask: vi.fn(), unarchiveTask: vi.fn(),
+      archiveAllDone: vi.fn(), refreshTasks: vi.fn(),
+    }));
+    localStorage.setItem("kb-dashboard-view-mode", "project");
+    localStorage.setItem(scopedKey("kb-dashboard-task-view", DEFAULT_PROJECT_ID), "list");
+
+    await renderAppAndWait("list-view");
+    fireEvent.click(screen.getByTestId("list-open-FN-1"));
+    await waitFor(() => {
+      expect(screen.getByRole("heading", { name: "Popup List Detail" })).toBeInTheDocument();
+      expect(screen.getByTestId("list-view")).toBeInTheDocument();
+    });
+
+    expect(dispatchNativeAndroidBack()).toBe(true);
+    dispatchPopState({ navIndex: 0 });
+    await waitFor(() => {
+      expect(screen.queryByRole("heading", { name: "Popup List Detail" })).toBeNull();
+      expect(screen.getByTestId("list-view")).toBeInTheDocument();
+    });
+    expect(dispatchNativeAndroidBack()).toBe(false);
+  });
+
   it("does not swallow native Android Back when no Fusion nav entry exists", async () => {
     await renderAppAndWait("board-view");