diff --git a/docs/architecture/pwa-self-hosted.md b/docs/architecture/pwa-self-hosted.md
index 22e3b59b0..a8329c97e 100644
--- a/docs/architecture/pwa-self-hosted.md
+++ b/docs/architecture/pwa-self-hosted.md
@@ -206,7 +206,10 @@ settings and guards read them in every build.
   throws `PlaylistWriteConflict`, and `PlaylistsService`'s per-playlist
   write queue runs the mutation again on a fresh read (a retry on the same,
   unread copy writes unconditionally, as before). Imports and start-up
-  migrations (`dbUpsertAppPlaylists`) write unconditionally. An M3U favorite
+  migrations (`dbUpsertAppPlaylists`) write unconditionally, and the store
+  refuses a document without an id. "Remove all" first lets queued
+  playlist writes land, and writes issued meanwhile wait until it is done.
+  An M3U favorite
   toggle goes through `transformPlaylistFavorites`, adding or removing that
   one channel on the favorites read at write time. After a write the store
   keeps its copy only when `X-Replaced-ETag` names the version its payload
@@ -224,7 +227,10 @@ settings and guards read them in every build.
   per page load (`iptvnator-server:unsent-writes:<instanceId>:<page>`). The
   tab remembers its page load in `sessionStorage`, so a reload takes its
   writes over and sends them first (the old copy goes only once the new one
-  is saved, at the latest with this page's next saved copy); the writes of a tab closed before it
+  is saved, at the latest with this page's next saved copy). A page marks
+  its record closed on `pagehide` (not into the back-forward cache), and
+  only a closed, stale or missing record is taken over: a duplicated tab,
+  which copies `sessionStorage`, leaves the running tab its writes; the writes of a tab closed before it
   could send them are queued, ahead of its own, by the next re-read in
   another tab once that tab's record has gone stale; the result replays the
   closed tab's edits first and this tab's newer ones last. Tabs never clear each other's.
@@ -289,7 +295,8 @@ settings and guards read them in every build.
   late 401 for a token replaced since (a new sign-in) changes nothing.
 - **Moving browser data.** `ServerMigrationService` offers, once per server
   instance (marker `iptvnator-server:migration:<instanceId>`), to move the
-  playlists this browser kept in IndexedDB (`planServerMigration`). A
+  playlists this browser kept in IndexedDB (`planServerMigration`), Stalker
+  rows from before the portal-mode flag normalized first. A
   playlist the server already has, by id or by source (Xtream server and
   user, Stalker portal and MAC, M3U URL), merges into the server's copy; the
   others upload with their ids. A merged playlist gains the browser
diff --git a/libs/services/src/lib/playlists.service.spec.ts b/libs/services/src/lib/playlists.service.spec.ts
index 08f5abd8e..6a6e4a864 100644
--- a/libs/services/src/lib/playlists.service.spec.ts
+++ b/libs/services/src/lib/playlists.service.spec.ts
@@ -1636,6 +1636,61 @@ describe('PlaylistsService', () => {
         );
     });
 
+    it('deletes everything only after queued writes, before later ones', async () => {
+        const order: string[] = [];
+        let finishWrite: () => void = () => undefined;
+        const electron = {
+            dbGetAppPlaylist: jest.fn(async () => {
+                order.push('read');
+                return { _id: 'p9', title: 'P', favorites: [] };
+            }),
+            dbGetAppPlaylists: jest.fn(async () => []),
+            dbGetAppState: jest.fn(async (key: string) =>
+                key === SQLITE_PLAYLIST_MIGRATION_FLAG ? '1' : null
+            ),
+            dbSetAppState: jest.fn(),
+            dbUpsertAppPlaylist: jest.fn(
+                () =>
+                    new Promise<void>((resolve) => {
+                        order.push('write');
+                        finishWrite = () => resolve();
+                    })
+            ),
+            dbUpsertAppPlaylists: jest.fn(),
+            dbDeleteAllPlaylists: jest.fn(async () => {
+                order.push('delete all');
+            }),
+        };
+        testWindow.electron = electron;
+        const service = createService();
+        // Microtasks only: a real timer would let other tests' late errors in.
+        const settle = async () => {
+            for (let i = 0; i < 50; i += 1) {
+                await Promise.resolve();
+            }
+        };
+
+        const first = firstValueFrom(
+            service.transformPlaylistFavorites('p9', (f) => [...f, 'a'])
+        );
+        await settle();
+        const removed = firstValueFrom(service.removeAll());
+        const later = firstValueFrom(
+            service.transformPlaylistFavorites('p9', (f) => [...f, 'b'])
+        );
+        await settle();
+        expect(order).toEqual(['read', 'write']);
+
+        finishWrite();
+        await first;
+        await removed;
+        await settle();
+        finishWrite();
+        await later;
+
+        expect(order).toEqual(['read', 'write', 'delete all', 'read', 'write']);
+    });
+
     it('runs a mutation again on a fresh read when the server refused it', async () => {
         const versions = [
             { _id: 'p9', title: 'P', favorites: ['a'] },
diff --git a/libs/services/src/lib/playlists.service.ts b/libs/services/src/lib/playlists.service.ts
index cbd1dd3f6..b9dc4733b 100644
--- a/libs/services/src/lib/playlists.service.ts
+++ b/libs/services/src/lib/playlists.service.ts
@@ -28,7 +28,6 @@ import {
     Channel,
     DbStores,
     extractStalkerItemId,
-    isFullStalkerPortalUrl,
     isM3uRecentlyViewedItem,
     M3uFavoriteChannel,
     M3uRecentlyViewedItem,
@@ -38,6 +37,7 @@ import {
     PlaylistUpdateState,
     StalkerPortalItem,
     normalizeStalkerDate,
+    withExplicitStalkerPortalFlag,
 } from '@iptvnator/shared/interfaces';
 import { PLAYLIST_DELETE_CLEANUP } from './playlist-delete-cleanup.token';
 import {
@@ -101,6 +101,8 @@ export class PlaylistsService {
     private startupMetas?: Promise<Playlist[]> | null;
     private indexedDbMigrationPromise: Promise<void> | null = null;
     private readonly playlistWriteQueues = new Map<string, Promise<unknown>>();
+    /** "Remove all" in progress: every playlist write waits for it. */
+    private deletingAll: Promise<void> = Promise.resolve();
 
     /** Electron bridge or server store; `null` means IndexedDB. */
     private get documentStore(): PlaylistDocumentStore | null {
@@ -242,19 +244,7 @@ export class PlaylistsService {
     }
 
     private withExplicitLegacyStalkerPortalFlag(playlist: Playlist): Playlist {
-        if (
-            !playlist?.macAddress ||
-            playlist.isFullStalkerPortal !== undefined
-        ) {
-            return playlist;
-        }
-
-        const portalUrl = playlist.portalUrl ?? playlist.url ?? '';
-
-        return {
-            ...playlist,
-            isFullStalkerPortal: isFullStalkerPortalUrl(portalUrl),
-        };
+        return withExplicitStalkerPortalFlag(playlist);
     }
 
     private collectStalkerMetadataMigrationUpdates(
@@ -412,8 +402,10 @@ export class PlaylistsService {
         operation: () => Promise<T>
     ): Observable<T> {
         return defer(() => {
-            const previous =
-                this.playlistWriteQueues.get(playlistId) ?? Promise.resolve();
+            const previous = Promise.all([
+                this.playlistWriteQueues.get(playlistId),
+                this.deletingAll,
+            ]);
             const next = previous.then(() => retryOnConflict(operation));
             const tail = next.then(
                 () => undefined,
@@ -1319,23 +1311,34 @@ export class PlaylistsService {
     }
 
     removeAll(): Observable<void> {
-        return defer(() =>
-            runWithPlaylistAuthorityReset(async () => {
-                if (this.usesDocumentStore) {
-                    await this.ensureElectronPlaylistMigrations();
-                    const store = this.documentStore;
-                    if (store) {
-                        this.startupMetas = null;
-                        await store.dbDeleteAllPlaylists();
-                        this.healthEvidence?.connections.next({});
-                    }
-                    return undefined;
-                }
+        // Writes already queued land first; new ones wait for the delete.
+        return defer(() => {
+            const pending = [...this.playlistWriteQueues.values()];
+            const run = Promise.all(pending).then(() => this.removeAllNow());
+            this.deletingAll = run.then(
+                () => undefined,
+                () => undefined
+            );
+            return run;
+        });
+    }
 
-                await firstValueFrom(this.dbService.clear(DbStores.Playlists));
+    private removeAllNow(): Promise<void> {
+        return runWithPlaylistAuthorityReset(async () => {
+            if (this.usesDocumentStore) {
+                await this.ensureElectronPlaylistMigrations();
+                const store = this.documentStore;
+                if (store) {
+                    this.startupMetas = null;
+                    await store.dbDeleteAllPlaylists();
+                    this.healthEvidence?.connections.next({});
+                }
                 return undefined;
-            })
-        );
+            }
+
+            await firstValueFrom(this.dbService.clear(DbStores.Playlists));
+            return undefined;
+        });
     }
 
     private normalizePortalRecentIdentity(value: unknown): string {
diff --git a/libs/services/src/lib/server-storage/server-migration.service.spec.ts b/libs/services/src/lib/server-storage/server-migration.service.spec.ts
index e7fc82173..daeb261c6 100644
--- a/libs/services/src/lib/server-storage/server-migration.service.spec.ts
+++ b/libs/services/src/lib/server-storage/server-migration.service.spec.ts
@@ -396,4 +396,26 @@ describe('ServerMigrationService', () => {
         expect(result.failed).toBeGreaterThan(0);
         expect(migration.browserDataMoved()).toBe(false);
     });
+
+    it('uploads a legacy Stalker row with its portal flag set', async () => {
+        TestBed.overrideProvider(NgxIndexedDBService, {
+            useValue: {
+                getAll: () =>
+                    of([
+                        {
+                            _id: 's1',
+                            title: 'Portal',
+                            macAddress: '00:1A:79:00:00:01',
+                            portalUrl: 'http://portal.test/stalker_portal/c',
+                        },
+                    ]),
+            },
+        });
+
+        await TestBed.inject(ServerMigrationService).moveBrowserData();
+
+        expect(session.documentStore.dbUpsertAppPlaylist).toHaveBeenCalledWith(
+            expect.objectContaining({ _id: 's1', isFullStalkerPortal: true })
+        );
+    });
 });
diff --git a/libs/services/src/lib/server-storage/server-migration.service.ts b/libs/services/src/lib/server-storage/server-migration.service.ts
index ddd97f361..f0f4193ec 100644
--- a/libs/services/src/lib/server-storage/server-migration.service.ts
+++ b/libs/services/src/lib/server-storage/server-migration.service.ts
@@ -7,6 +7,7 @@ import {
     type Playlist,
     type ServerUserStateNamespace,
     type ServerUserStateResponse,
+    withExplicitStalkerPortalFlag,
 } from '@iptvnator/shared/interfaces';
 import {
     combineUserData,
@@ -322,10 +323,13 @@ export class ServerMigrationService {
         return failed;
     }
 
-    private readBrowserPlaylists(): Promise<Playlist[]> {
-        return firstValueFrom(
+    private async readBrowserPlaylists(): Promise<Playlist[]> {
+        const playlists = await firstValueFrom(
             this.dbService.getAll<Playlist>(DbStores.Playlists)
         );
+        // A browser that skipped the Stalker metadata migration still has
+        // rows without the explicit portal flag.
+        return playlists.map(withExplicitStalkerPortalFlag);
     }
 
     private readMarker(): string | null {
diff --git a/libs/services/src/lib/server-storage/server-playlist-document-store.spec.ts b/libs/services/src/lib/server-storage/server-playlist-document-store.spec.ts
index 0d753c547..ae5188c43 100644
--- a/libs/services/src/lib/server-storage/server-playlist-document-store.spec.ts
+++ b/libs/services/src/lib/server-storage/server-playlist-document-store.spec.ts
@@ -233,6 +233,15 @@ describe('ServerPlaylistDocumentStore', () => {
         });
     });
 
+    it('refuses a document without an id', async () => {
+        const { api, store } = setup();
+
+        await expect(
+            store.dbUpsertAppPlaylist({ title: 'Orphan' } as Playlist)
+        ).rejects.toThrow('without an id');
+        expect(api.sendJson).not.toHaveBeenCalled();
+    });
+
     it('writes imports as they are', async () => {
         const { api, store } = setup();
         api.request.mockResolvedValueOnce(fakeResponse(200, doc, '"b.0.1"'));
diff --git a/libs/services/src/lib/server-storage/server-playlist-document-store.ts b/libs/services/src/lib/server-storage/server-playlist-document-store.ts
index bad254eeb..7e41995b4 100644
--- a/libs/services/src/lib/server-storage/server-playlist-document-store.ts
+++ b/libs/services/src/lib/server-storage/server-playlist-document-store.ts
@@ -147,7 +147,11 @@ export class ServerPlaylistDocumentStore implements PlaylistDocumentStore {
         playlist: Playlist,
         conditional: boolean
     ): Promise<ElectronBridgeResult> {
-        const id = playlist._id;
+        const id = playlist?._id;
+        if (!id) {
+            // A mutation that ran after its playlist was deleted.
+            throw new Error('A playlist without an id cannot be stored.');
+        }
         const path = `/playlists/${encodeURIComponent(id)}`;
         const payloadEtag = this.servedPayloadEtag(playlist);
         // The version it was read at: of its payload, else of the copy it
diff --git a/libs/services/src/lib/server-storage/server-storage-session.ts b/libs/services/src/lib/server-storage/server-storage-session.ts
index ffd5886a9..0d90b259c 100644
--- a/libs/services/src/lib/server-storage/server-storage-session.ts
+++ b/libs/services/src/lib/server-storage/server-storage-session.ts
@@ -137,9 +137,13 @@ export class ServerStorageSession {
                 void this.refresh();
             }
         });
-        window.addEventListener('pagehide', () =>
-            this.userData.flushWithKeepalive()
-        );
+        window.addEventListener('pagehide', (event) => {
+            this.userData.flushWithKeepalive();
+            // Not into the back-forward cache: the page is gone for good.
+            if (!event.persisted) {
+                this.userData.close();
+            }
+        });
         setInterval(() => {
             this.userData.touch();
             // Also online: a write the server refused (a 5xx) or a first
diff --git a/libs/services/src/lib/server-storage/server-unsent-writes.ts b/libs/services/src/lib/server-storage/server-unsent-writes.ts
index 42a9a9a0d..efa86f423 100644
--- a/libs/services/src/lib/server-storage/server-unsent-writes.ts
+++ b/libs/services/src/lib/server-storage/server-unsent-writes.ts
@@ -292,7 +292,48 @@ export function saveDeferredEdits(
     }
 }
 
-type UnconfirmedRegistry = Record<string, { at: number; keys: string[] }>;
+/** `closed`: the page unloaded (not into the back-forward cache). */
+type UnconfirmedRegistry = Record<
+    string,
+    { at: number; keys: string[]; closed?: boolean }
+>;
+
+/** Marks a page load's record as unloaded: a reload may take it over. */
+export function markClosed(
+    local: UserDataStorage,
+    instanceId: string,
+    page: string
+): void {
+    const registry = readRegistry(local, instanceId);
+    if (!registry[page]) {
+        return;
+    }
+    registry[page] = { ...registry[page], closed: true };
+    try {
+        local.setItem(unconfirmedKey(instanceId), JSON.stringify(registry));
+    } catch {
+        // Storage full: the record goes stale instead.
+    }
+}
+
+/**
+ * Whether a page load still runs: it has a fresh record and did not
+ * unload. A duplicated tab copies the tab's page load but must not take
+ * over its saved writes.
+ */
+export function pageIsLive(
+    local: UserDataStorage,
+    instanceId: string,
+    page: string,
+    now = Date.now()
+): boolean {
+    const record = readRegistry(local, instanceId)[page];
+    return (
+        !!record &&
+        !record.closed &&
+        now - Number(record.at) < UNCONFIRMED_TTL_MS
+    );
+}
 
 function readRegistry(
     local: UserDataStorage,
diff --git a/libs/services/src/lib/server-storage/server-user-data-storage.spec.ts b/libs/services/src/lib/server-storage/server-user-data-storage.spec.ts
index ef48b93aa..0f4e1ffb5 100644
--- a/libs/services/src/lib/server-storage/server-user-data-storage.spec.ts
+++ b/libs/services/src/lib/server-storage/server-user-data-storage.spec.ts
@@ -490,7 +490,8 @@ describe('ServerUserDataStorage', () => {
             },
         ]);
 
-        // Reload: a new instance over the same browser storage.
+        // Reload: the page unloads, a new instance over the same storage.
+        first.storage.close();
         const api = {
             ...first.api,
             sendJson: jest.fn().mockResolvedValue(undefined),
@@ -621,6 +622,7 @@ describe('ServerUserDataStorage', () => {
             'xtream-favorites',
             JSON.stringify({ p1: ['mine'] })
         );
+        first.storage.close();
 
         const api = {
             ...first.api,
diff --git a/libs/services/src/lib/server-storage/server-user-data-storage.ts b/libs/services/src/lib/server-storage/server-user-data-storage.ts
index dd0cfbfe4..2e18749f9 100644
--- a/libs/services/src/lib/server-storage/server-user-data-storage.ts
+++ b/libs/services/src/lib/server-storage/server-user-data-storage.ts
@@ -22,8 +22,10 @@ import {
 import { UserDataWriteQueue } from './server-user-data-queue';
 import {
     claimCache,
+    markClosed,
     markUnconfirmed,
     orphanedPages,
+    pageIsLive,
     othersUnconfirmed,
     readDeferredEdits,
     readUnsentWrites,
@@ -98,11 +100,17 @@ export class ServerUserDataStorage implements UserDataStorage {
         });
         claimCache(local, instanceId);
         const previous = swapPage(tabStore, instanceId, this.tabId);
-        if (previous) {
+        // A duplicated tab copies the page load of a tab that still runs.
+        if (previous && !pageIsLive(local, instanceId, previous)) {
             this.takeOver(previous);
         }
     }
 
+    /** The page unloads: a reload of this tab may take its writes over. */
+    close(): void {
+        markClosed(this.local, this.instanceId, this.tabId);
+    }
+
     /**
      * A reload of this tab: the writes its last page load could not confirm
      * go out with the first flush, and the first read keeps them.
@@ -191,7 +199,7 @@ export class ServerUserDataStorage implements UserDataStorage {
     }
 
     getItem(key: string): string | null {
-        if (!this.isSynced(key)) {
+        if (!isServerUserStateNamespace(key)) {
             return this.local.getItem(key);
         }
         const value = this.cache.read(key);
@@ -200,7 +208,7 @@ export class ServerUserDataStorage implements UserDataStorage {
     }
 
     setItem(key: string, value: string): void {
-        if (this.isSynced(key)) {
+        if (isServerUserStateNamespace(key)) {
             this.write(key, value);
         } else {
             this.local.setItem(key, value);
@@ -208,7 +216,7 @@ export class ServerUserDataStorage implements UserDataStorage {
     }
 
     removeItem(key: string): void {
-        if (this.isSynced(key)) {
+        if (isServerUserStateNamespace(key)) {
             this.write(key, null);
         } else {
             this.local.removeItem(key);
@@ -395,10 +403,6 @@ export class ServerUserDataStorage implements UserDataStorage {
         this.adoptClosedTabs();
     }
 
-    private isSynced(key: string): key is ServerUserStateNamespace {
-        return isServerUserStateNamespace(key);
-    }
-
     private queueChanges(
         namespace: ServerUserStateNamespace,
         next: Record<string, unknown>,
diff --git a/libs/services/src/lib/server-storage/server-user-data-sync.spec.ts b/libs/services/src/lib/server-storage/server-user-data-sync.spec.ts
index 5d911c021..a3cc6cff7 100644
--- a/libs/services/src/lib/server-storage/server-user-data-sync.spec.ts
+++ b/libs/services/src/lib/server-storage/server-user-data-sync.spec.ts
@@ -421,6 +421,7 @@ describe('ServerUserDataStorage with other devices', () => {
         before.setItem('xtream-favorites', JSON.stringify({ p1: ['S'] }));
         expect(server.state['xtream-favorites']['p1']).toEqual(['S', 'X']);
 
+        before.close();
         const reloaded = open();
         await reloaded.hydrate();
         await reloaded.flush();
@@ -823,6 +824,7 @@ describe('ServerUserDataStorage with other devices', () => {
             setItem(key, value);
         };
         const kept = saved()[0];
+        before.close();
         const reloaded = new ServerUserDataStorage(
             offline as never,
             local,
@@ -869,6 +871,7 @@ describe('ServerUserDataStorage with other devices', () => {
         await before.flush();
 
         // Reloaded: the recovered write fails once, the read works.
+        before.close();
         const send = server.api.sendJson.getMockImplementation();
         const api = {
             ...server.api,
@@ -920,6 +923,7 @@ describe('ServerUserDataStorage with other devices', () => {
         await before.hydrate();
         before.setItem('xtream-favorites', JSON.stringify({ p1: ['S', 'X'] }));
         await before.flush();
+        before.close();
 
         const send = server.api.sendJson.getMockImplementation();
         const reloaded = new ServerUserDataStorage(
@@ -967,4 +971,50 @@ describe('ServerUserDataStorage with other devices', () => {
         expect(phone.hasUnsentWrites()).toBe(false);
         expect(favorites(phone)).toEqual({});
     });
+
+    it('leaves a still running tab its saved writes when the tab is duplicated', async () => {
+        const server = fakeServer({ 'xtream-favorites': { p1: ['S'] } });
+        const local = memoryStorage();
+        const tabStore = memoryStorage();
+        const offline = {
+            ...server.api,
+            sendJson: jest
+                .fn()
+                .mockRejectedValue(new ServerApiError(0, 'network', 'offline')),
+        };
+        const original = new ServerUserDataStorage(
+            offline as never,
+            local,
+            jest.fn(),
+            'default',
+            tabStore
+        );
+        await original.hydrate();
+        original.setItem(
+            'xtream-favorites',
+            JSON.stringify({ p1: ['S', 'X'] })
+        );
+        await original.flush();
+
+        // A duplicated tab starts with a copy of the tab's own storage.
+        const copy = memoryStorage();
+        for (const [key, value] of tabStore.values) {
+            copy.setItem(key, value);
+        }
+        const duplicate = new ServerUserDataStorage(
+            offline as never,
+            local,
+            jest.fn(),
+            'default',
+            copy
+        );
+
+        expect(duplicate.hasUnsentWrites()).toBe(false);
+        expect(original.hasUnsentWrites()).toBe(true);
+        expect(
+            [...local.values.keys()].filter((key) =>
+                key.startsWith('iptvnator-server:unsent-writes:')
+            )
+        ).toHaveLength(1);
+    });
 });
diff --git a/libs/shared/interfaces/src/lib/stalker-portal-mode.util.ts b/libs/shared/interfaces/src/lib/stalker-portal-mode.util.ts
index 4fcc23362..dbaadc3ec 100644
--- a/libs/shared/interfaces/src/lib/stalker-portal-mode.util.ts
+++ b/libs/shared/interfaces/src/lib/stalker-portal-mode.util.ts
@@ -26,6 +26,29 @@ export function isFullStalkerPortalUrl(url: string): boolean {
     return url.includes('/stalker_portal') || url.includes('/server/load.php');
 }
 
+/**
+ * A Stalker playlist saved before the explicit flag existed, with the flag
+ * set from its URL; any other playlist comes back unchanged.
+ */
+export function withExplicitStalkerPortalFlag<
+    T extends {
+        macAddress?: string;
+        isFullStalkerPortal?: boolean;
+        portalUrl?: string;
+        url?: string;
+    },
+>(playlist: T): T {
+    if (!playlist?.macAddress || playlist.isFullStalkerPortal !== undefined) {
+        return playlist;
+    }
+    return {
+        ...playlist,
+        isFullStalkerPortal: isFullStalkerPortalUrl(
+            playlist.portalUrl ?? playlist.url ?? ''
+        ),
+    };
+}
+
 /**
  * Whether a playlist should use the full-portal auth lifecycle
  * (handshake, Bearer token, watchdog).