User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.99 Safari/537.36 Steps to reproduce: I have a page with 2 or more flash files on it. The flash files are included with wmode=transparent. And i have a container with a css animation on it. Steps to reproduce: - Resize the browser to 1024x768px. Bug 1: - Load the file flash-wmode-transparent.html. Bug 2: - Reload the page until only one flash is shown. Current Workaround: If i include the flash files with wmode=opaque, the rendering is fine. --> File flash-wmode-opaque.html Actual results: Bug 1: If I load the page, the container with css animation issn't displayed. Only when i scroll, the container appears. --> bug-1.jpg Bug 2: Sometimes, the second flash issnt loaded. If that happend, the rendering on real pages is destroyed. --> bug-2.jpg If you scroll down and up (or switch the tab), the browser will redraw the rendering and everything is fine. Expected results: Bug 1: The Container with animated should always be visible. Bug 2: Both Flash files should always be visible. --> after-scroll.jpg

Did it use to work in the past with previous versions of Firefox?

Just test the examples in Firefox 33 - 35: I can reproduce both Bugs in Firefox 34.0.5 and Firefox 35.0 on Win 7. I can not reproduce these Bugs on Firefox 33.1.1 on Win 7. I can not reproduce these Bugs on Firefox 35.0 on Mac 10.10.1.

Pushlog : https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=6eded676da83&tochange=9b44cf686aba Regressed by: Bug 947781

This might be related to readback layers. I'll have a look at this.

[Tracking Requested - why for this release]: We're tracking similar bug 1127459 and bug 1132432 and this one has good STR.

Tracking as per comment 5. Milan - As a reminder, we have limited time to fix issues in 37.

I expect this bug is a duplicate of bug 1127459 and bug 1132432 (both already tracked), so it doesn't really change that much of a picture for 37. Whether we get a fix for any of those, and whether that fix is appropriate for a beta uplift remains to be seen.

Please test against this build: https://tbpl.mozilla.org/?tree=Mozilla-Inbound&rev=91e84603aaa0 My expectation is that this is now fixed.

I can't reproduce the mentioned bug in this build. Tryed the test case above and some other test cases. So it seems to be fixed. :-) Great Work. Thanks.

Fixed by bug 1132432.