--- a/testing/web-platform/tests/webdriver/tests/support/fixtures.py
+++ b/testing/web-platform/tests/webdriver/tests/support/fixtures.py
@@ -71,16 +71,17 @@ def _restore_windows(session):
     for window in _windows(session, exclude=[current_window]):
         session.window_handle = window
         if len(session.handles) > 1:
             session.close()
 
     session.window_handle = current_window
 
 
+@ignore_exceptions
 def _switch_to_top_level_browsing_context(session):
     """If the current browsing context selected by WebDriver is a
     `<frame>` or an `<iframe>`, switch it back to the top-level
     browsing context.
     """
     session.switch_frame(None)