Navigation initiated by history.back() should overwrite child frame reload, which was started eralier and did not finish yet. History state at the end should reflect the back() call. ============== Back Forward List ============== http://127.0.0.1:8000/navigation/back-during-child-frame-reload.html about:blank (in frame "-->") curr-> http://127.0.0.1:8000/navigation/back-during-child-frame-reload.html?one about:blank (in frame "-->") http://127.0.0.1:8000/navigation/back-during-child-frame-reload.html?one?two about:blank (in frame "-->") ===============================================