diff --git a/frontend/src/app/components/Layout/AppShell.tsx b/frontend/src/app/components/Layout/AppShell.tsx
index 2b47615c..c28c51e8 100644
--- a/frontend/src/app/components/Layout/AppShell.tsx
+++ b/frontend/src/app/components/Layout/AppShell.tsx
@@ -255,7 +255,9 @@ const AppShell: React.FC = () => {
       dispatch(setPendingBrowserUrl(url));
       const lastId = (window as any).__openswarm_last_dashboard_id as string | undefined;
       const firstDashboard = dashboardList[0];
-      const targetId = lastId || firstDashboard?.id;
+      // Only navigate to lastId if it's a REAL dashboard: a stale localStorage id for a deleted dashboard used to route to /dashboard/<phantom>, which 404s and re-fires the layout wipe (drops your cards / breaks a drag).
+      const lastIsReal = !!lastId && dashboardList.some((d) => d.id === lastId);
+      const targetId = (lastIsReal ? lastId : undefined) || firstDashboard?.id;
       if (targetId) {
         navigate(`/dashboard/${targetId}`);
       } else {
diff --git a/frontend/src/app/pages/Dashboard/hooks/lifecycle/useDashboardLifecycle.ts b/frontend/src/app/pages/Dashboard/hooks/lifecycle/useDashboardLifecycle.ts
index bc4f2f55..d2d65512 100644
--- a/frontend/src/app/pages/Dashboard/hooks/lifecycle/useDashboardLifecycle.ts
+++ b/frontend/src/app/pages/Dashboard/hooks/lifecycle/useDashboardLifecycle.ts
@@ -113,13 +113,16 @@ export function useDashboardLifecycle({
 
   useEffect(() => {
     if (!dashboardId) return;
-    hasFittedRef.current = false;
-    restoredExpandedRef.current = false;
-    setOutputsRefetched(false);
-    dispatch(resetLayout({ keepBrowserIds: getKeepAliveBrowserIds() }));
-    // CRITICAL path: these populate the cards the user expects to see on first paint. Don't defer.
-    dispatch(fetchSessions({ dashboardId }));
-    dispatch(fetchLayout({ dashboardId }));
+    // Never wipe+reload the layout while a card drag or marquee is in flight: a spurious mid-gesture nav (e.g. a phantom-dashboard round-trip) would unmount the card under the cursor and the drag silently dies. You can't switch dashboards while holding a drag, so any reset firing now is spurious. The shield class is up for exactly that window. Handlers below still install.
+    if (!document.body.classList.contains('dashboard-marquee-active')) {
+      hasFittedRef.current = false;
+      restoredExpandedRef.current = false;
+      setOutputsRefetched(false);
+      dispatch(resetLayout({ keepBrowserIds: getKeepAliveBrowserIds() }));
+      // CRITICAL path: these populate the cards the user expects to see on first paint. Don't defer.
+      dispatch(fetchSessions({ dashboardId }));
+      dispatch(fetchLayout({ dashboardId }));
+    }
     const cleanupBrowserHandler = initBrowserCommandHandler();
     // Global broadcasts (spawned browser cards) skip the replay log, so a socket gap loses them; a reconnect refetch is the only way they return.
     const unsubReconnect = dashboardWs.on('dashboard:reconnected', () => {