This is almost the same test as dynamic-frame-creation-order-onload-handler.html except that the dynamic frames are created from an inline script, rather than in response to an onload event. If we enable back-forward cache, back navigation doesn't run inline script and thus this test fails. Frame creation order during this page load: Created Created Final frame URLs during this page load (should match the list above): URL of left is http://127.0.0.1:8000/history/resources/red.html URL of right is http://127.0.0.1:8000/history/resources/green.html Dynamically created frames: