Created attachment 226340 [details] Test Case In Safari nightly r165260, when I try to click on the transitioning element, it doesn't dispatch a click event most of the time. However, sometimes it starts dispatching click events after I click on it a bunch of times. Works as expected in Chrome Canary 35.0.1871.0 and Firefox 27.0.1. Interestingly, the bug repros in Chrome Stable 33.0.1750.146.
Does this reproduce in Safari 7? Can you try some other nightlies? Would be useful to know when this regressed.
(In reply to comment #1) > Does this reproduce in Safari 7? Can you try some other nightlies? Would be useful to know when this regressed. Yes, it repros in Safari 7.0.2 (9537.74.9) on my Mac. I'll try some nightlies when http://nightly.webkit.org comes back up.
It repros at least as far back as this build: r149492 2013-05-02 21:04:01 GMT r149492.dmg">http://builds.nightly.webkit.org/files/trunk/mac/WebKit-SVN-r149492.dmg I had to use an older Mac with 10.8.4 to run that build. I don't have a Mac old enough to test father back.
This is an regression in the accelerated compositing code exclusively between shipping Safari 5.1.9 (6534.59.8) and Safari Version 6.1 (7537.71) with r90316. The test doesn't reproduce in shipping Safari 5.1.9 (6534.59.8) on Mac OS 10.6.8 (10K549) regardless of the state of accelerated compositing. The test reproduces only with accelerated compositing enabled in Safari Version 6.1 (7537.71) with r90316 on Mac OS X 10.7.5 (11G63). Unfortunately I ran into limitations running nighties on Mac OS 10.6.8 and Mac OS X 10.7.5 that prevented me from further narrowing this range :(
Seems reliable to me with Safari 16: hover works as expected and I always get an alert when clicking.