diff --git a/src/chromium/crPage.ts b/src/chromium/crPage.ts
index 2dc335ddf8..da09c67343 100644
--- a/src/chromium/crPage.ts
+++ b/src/chromium/crPage.ts
@@ -104,8 +104,8 @@ export class CRPage implements PageDelegate {
       return;
     // Frame id equals target id.
     const frame = this._page._frameManager.frame(targetId);
-    assert(frame);
-    this._page._frameManager.removeChildFramesRecursively(frame);
+    if (frame)
+      this._page._frameManager.removeChildFramesRecursively(frame);
     frameSession.dispose();
     this._sessions.delete(targetId);
   }