1226297 - It's possible to accidentally hover the #fullscr-toggler and cancel the fullscreen transition

Status: NEW

(Firefox :: General, defect)

Description

[arni2033]

>>>   My Info:   Win7_64, Nightly 45, 32bit, ID 20151119030404
STR:
1. Maximize firefox window
2. Move mouse pointer to the center of navigation toolbar
3. Press F11 to switch to fullscreen mode
4. While transition is performing, move mouse pointer up and down trying to hover #fullscr-toggler

Result:       
 Fullscreen transition is aborted.
> screencast:   https://dl.dropboxusercontent.com/s/jbd1g5zntc908zf/video%20-%20It%27s%20possible%20to%20accidentally%20hover%20the%20%23fullscr-toggler%20and%20cancel%20the%20fullscreen%20transition.webm?dl=0

Expectations:   (A) or (B)
 A) Transition shouldn't be canceled (#fullscr-toggler shouldn't be visible until transition finishes)
 B) Transition NEVER should be triggered when #navigator-toolbox is hovered

It was regressed between 2015-05-05 and 2015-05-06 by bug 947854:
> pushlog_url:   https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=d96afcb35853ae1f3b934c3b08b5f5932241846c&tochange=f5c29147aa664274313918bdca3abab39547fac9