1) Load a tab with http://dolske.net/mozilla/tests/prompt/onbeforeunload.html 2) Trigger Forget button 3) onbeforeload prompt comes up, a bit of weirdness with the Forget panel not going away Ideally we should suppress the onbeforeunload entirely, as the Forget panel is pretty clear about what it's doing (in red!), and for the intended usecases the prompt it more likely to be an annoyance.

> 3) onbeforeload prompt comes up, a bit of weirdness with the Forget panel > not going away Specifically: upon clicking the "Forget!" action button, the onbeforeunload prompt is shown under the Forget panel (which remains open). If you click "Leave Page" in the onbeforeunload prompt, the rest of the Forget action completes successfully. Clicking the "Forget!" button a second time (while it's open) will work correctly too.

(In reply to Justin Dolske [:Dolske] from comment #1) > > 3) onbeforeload prompt comes up, a bit of weirdness with the Forget panel > > not going away > > Specifically: upon clicking the "Forget!" action button, the onbeforeunload > prompt is shown under the Forget panel (which remains open). If you click > "Leave Page" in the onbeforeunload prompt, the rest of the Forget action > completes successfully. Clicking the "Forget!" button a second time (while > it's open) will work correctly too. Huh, we should probably just manually close the popup, at least. I'm not sure if we can prevent beforeunload from firing completely with the currently exposed APIs. Of course, we could add APIs, but we can't backport that to 33.1...