1043498 - Weird box shows up during/behind CSS animation

Status: RESOLVED DUPLICATE of bug 1041530

(Firefox :: Untriaged, defect)

Description

[Luís Miguel [:quicksaver] (not reading bugmail)]

Attachment: Rendering bug during animation

STR:
1) Latest nightly, clean profile
2) Go to https://addons.mozilla.org/en-US/firefox/addon/the-fox-only-better/, install latest dev version (in the development channel, currently it's 1.1b8)
3) Go to the add-ons preferences and enable the animation "GiT's Hinge Effect"
4) In the main browser window, move the mouse over and out of the top chrome to show and hide the toolbars.
-> A weird looking box appears "behind" the chrome while the animation is running (see screenshot). This won't happen if the window is below a certain width btw.

The animation is very simple, it just adds a perspective to the navigator-toolbox, and applies a transform:rotateX() on the toolbars container (added by the add-on) to make them turn down like that. Full style:
> #navigator-toolbox[slimAnimation="hinge"] #theFoxOnlyBetter-slimChrome-container:not([mini]):not([hover]) {
> 	transition: opacity 0s linear .5s, transform .5s linear 0s;
> 	transform: rotateX(-90deg);
> }
> #navigator-toolbox[slimAnimation="hinge"] #theFoxOnlyBetter-slimChrome-container[mini]:not([hover]),
> #navigator-toolbox[slimAnimation="hinge"] #theFoxOnlyBetter-slimChrome-container:not([mini])[hover] {
> 	transition: transform .25s ease-in 0s;
> }
> #navigator-toolbox[slimAnimation="hinge"] #theFoxOnlyBetter-slimChrome-container {
> 	transform-origin: top;
> }
> #navigator-toolbox[slimAnimation="hinge"]  {
> 	perspective: 1500px;
> }

This was working fine until a few days ago, with no visual bugs that I was aware of. 33.0a1-2014-07-20 was the last version that I've verified was working properly, 34.0a1-2014-07-21 has the bug.

I tried checking the pushlog for all the changes between those versions (http://hg.mozilla.org/mozilla-central/pushloghtml?startdate=2014-07-20+00%3A00%3A00&enddate=2014-07-21+23%3A59%3A59), but I couldn't find any likely culprit.

Comment 1

[Luís Miguel [:quicksaver] (not reading bugmail)]

Robert, do you think bug 1022612 is the cause for this, and if so is this a duplicate of any of its dependencies? I don't understand enough about that bug to assert that myself.

Comment 2

[Robert O'Callahan (:roc) (email my personal email if necessary)]

Looks like a dup of bug 1041530. Please retest when that bug lands.

Comment 3

[Luís Miguel [:quicksaver] (not reading bugmail)]

Re-tested and verified as fixed with today's nightly after bug 1041530 landed.