Bugzilla#1220143, Relevant (though unclear) spec in UI Events

Focus on this button and press Space or Enter:

Expected: alert button gets focus.
Actural: alert button gets focus and was clicked.


Firefox 74 Chrome 80 Safari 13
Pressing Space on #focus triggers click on #alert
(via keyup?)
Yes No No
Pressing Enter on #focus triggers click on #alert
(via keypress?)
Yes Yes Yes