Comment 110 for bug 66566

I made a small sheet to better understand what changes here, please check and comment if something doesn't look correct.
https://docs.google.com/spreadsheets/d/1VVEVjyIYRZIFteM71j5bJhENa2xXT82gaikr0WgpKLA/edit#gid=0

I didn't test the patch, I just assumed, on IRC Gijs said it's likely different.
Anyway, I added a row with the behavior I'm suggesting, that is pretty much the same as Chromium, apart ALT+Enter on the Mac.