diff --git a/packages/frontend/component/src/components/page-list/page-content-preview.tsx b/packages/frontend/component/src/components/page-list/page-content-preview.tsx
index 9dcc38b12..29c8b2e53 100644
--- a/packages/frontend/component/src/components/page-list/page-content-preview.tsx
+++ b/packages/frontend/component/src/components/page-list/page-content-preview.tsx
@@ -1,4 +1,3 @@
-import { assertExists } from '@blocksuite/global/utils';
 import type { Workspace } from '@blocksuite/store';
 import { useBlockSuitePagePreview } from '@toeverything/hooks/use-block-suite-page-preview';
 import { useBlockSuiteWorkspacePage } from '@toeverything/hooks/use-block-suite-workspace-page';
@@ -12,7 +11,6 @@ interface PagePreviewInnerProps {
 
 const PagePreviewInner = ({ workspace, pageId }: PagePreviewInnerProps) => {
   const page = useBlockSuiteWorkspacePage(workspace, pageId);
-  assertExists(page);
   const previewAtom = useBlockSuitePagePreview(page);
   const preview = useAtomValue(previewAtom);
   return preview ? preview : null;
diff --git a/packages/frontend/core/src/hooks/use-workspace.ts b/packages/frontend/core/src/hooks/use-workspace.ts
index b8532bd38..dc3937ad0 100644
--- a/packages/frontend/core/src/hooks/use-workspace.ts
+++ b/packages/frontend/core/src/hooks/use-workspace.ts
@@ -1,6 +1,8 @@
-import type { AffineOfficialWorkspace } from '@affine/env/workspace';
+import {
+  type AffineOfficialWorkspace,
+  WorkspaceFlavour,
+} from '@affine/env/workspace';
 import { rootWorkspacesMetadataAtom } from '@affine/workspace/atom';
-import { assertExists } from '@blocksuite/global/utils';
 import type { Workspace } from '@blocksuite/store';
 import { getBlockSuiteWorkspaceAtom } from '@toeverything/infra/__internal__/workspace';
 import type { Atom } from 'jotai';
@@ -24,12 +26,21 @@ export function useWorkspace(workspaceId: string): AffineOfficialWorkspace {
   const workspace = useAtomValue(workspaceAtom);
   if (!workspaceWeakMap.has(workspace)) {
     const baseAtom = atom(async get => {
-      const metadata = await get(rootWorkspacesMetadataAtom);
-      const flavour = metadata.find(({ id }) => id === workspaceId)?.flavour;
-      assertExists(flavour, 'workspace flavour not found');
+      const metadataList = await get(rootWorkspacesMetadataAtom);
+      const flavour = metadataList.find(({ id }) => id === workspaceId)
+        ?.flavour;
+
+      if (!flavour) {
+        // when last workspace is removed, we may encounter this warning. it should be fine
+        console.warn(
+          'workspace not found in rootWorkspacesMetadataAtom, maybe it is removed',
+          workspaceId
+        );
+      }
+
       return {
         id: workspaceId,
-        flavour,
+        flavour: flavour ?? WorkspaceFlavour.LOCAL,
         blockSuiteWorkspace: workspace,
       };
     });
diff --git a/packages/frontend/hooks/src/use-block-suite-page-preview.ts b/packages/frontend/hooks/src/use-block-suite-page-preview.ts
index ccb828582..fc630c5f2 100644
--- a/packages/frontend/hooks/src/use-block-suite-page-preview.ts
+++ b/packages/frontend/hooks/src/use-block-suite-page-preview.ts
@@ -17,8 +17,12 @@ export const getPagePreviewText = (page: Page) => {
   return text.slice(0, 300);
 };
 
-export function useBlockSuitePagePreview(page: Page): Atom<string> {
-  if (weakMap.has(page)) {
+const emptyAtom = atom<string>('');
+
+export function useBlockSuitePagePreview(page: Page | null): Atom<string> {
+  if (page === null) {
+    return emptyAtom;
+  } else if (weakMap.has(page)) {
     return weakMap.get(page) as Atom<string>;
   } else {
     const baseAtom = atom<string>(getPagePreviewText(page));