diff --git a/packages/blocks/src/root-block/widgets/format-bar/format-bar.ts b/packages/blocks/src/root-block/widgets/format-bar/format-bar.ts
index ccb688615f66..4b5457c324cf 100644
--- a/packages/blocks/src/root-block/widgets/format-bar/format-bar.ts
+++ b/packages/blocks/src/root-block/widgets/format-bar/format-bar.ts
@@ -161,7 +161,10 @@ export class AffineFormatBarWidget extends WidgetElement {
         let targetRect: DOMRect | null = null;
         if (this.displayType === 'text' || this.displayType === 'native') {
           const range = this.nativeRange;
-          assertExists(range);
+          if (!range) {
+            this._reset();
+            return;
+          }
           targetRect = range.getBoundingClientRect();
         } else if (this.displayType === 'block') {
           const blockElement = this._selectedBlockElements[0];