fix undefined error

packages/app/src/components/PageComment.tsx

@@ -16,7 +16,6 @@ import { useSWRxPageComment } from '../stores/comment';
 
 import { Comment } from './PageComment/Comment';
 import { CommentEditorProps } from './PageComment/CommentEditor';
-import { CommentEditorLazyRenderer } from './PageComment/CommentEditorLazyRenderer';
 import { DeleteCommentModalProps } from './PageComment/DeleteCommentModal';
 import { ReplyComments } from './PageComment/ReplyComments';
 import { PageCommentSkelton } from './PageCommentSkelton';
@@ -142,6 +141,10 @@ export const PageComment: FC<PageCommentProps> = memo((props:PageCommentProps):
     );
   }
 
+  if (currentPage.revision == null) {
+    return <></>;
+  }
+
   const generateCommentElement = (comment: ICommentHasId) => (
     <Comment
       comment={comment}

packages/app/src/components/PageContentFooter.tsx

@@ -15,7 +15,7 @@ export const PageContentFooter = memo((): JSX.Element => {
 
   const { data: page } = useSWRxCurrentPage();
 
-  if (page == null || page.revision === undefined) {
+  if (page == null || page.revision == null) {
     return <></>;
   }