Description of problem: Firefox in my newly installed fedora 14 x86_64 system with a RV610 radeon card, text in an area of the screen that is partially overlapped by another window is completely shredded when I scroll the firefox main window. (I'll attach a screen shot). On the same hardware running fedora 13 I've never had this happen. I submit this as a firefox bug rather than a radeon driver bug because of the other thing that happens: When I move the cursor out of the firefox window and it loses focus, the shredded text gets redrawn correctly. That makes me believe firefox is trying to be way too clever processing redraw events. Version-Release number of selected component (if applicable): firefox-3.6.12-1.fc14.x86_64 xorg-x11-drv-ati-6.13.1-0.3.20100705git37b348059.fc14.x86_64 How reproducible: Seems to happen pretty consistently. Steps to Reproduce: 1.see above 2. 3. Actual results: shredded text Expected results: correctly redrawn text as it scrolls out from under another window Additional info: The ati card is: 01:00.0 VGA compatible controller: ATI Technologies Inc RV610 video device [Radeon HD 2400 PRO]
Created attachment 457562 [details] screenshot of shredded firefox window
More evidence that this if firefox, not radeon driver: If I look at the same page in konqueror and overlap the windows the same way, text that scrolls out from under the xterm is drawn perfectly by konqueror, only firefox seems to want to shred it. I also tried this with a brand new user so no leftover ~/.mozilla nonsense could have been inherited from the old /home directory I restored, but the text shredding was the same. I briefly rebooted into fedora 13 and confirmed that I do not see the same shredding when I setup the same window overlap and scrolling.
It's known issue already fixed in upcoming Firefox 4.
Just curious, is there a bugzilla or patch or something somewhere that points to this known issue fix? All I can find when searching is more reports of similar bugs like this one: https://bugzilla.mozilla.org/show_bug.cgi?id=576795
You need to search for gfx/layer bugs, the layer code was heavily updated in ff4 because of a new layer acceleration model and I guess the fix of this but is a side effect of it.
This definitely appears to be another instance of cairo changes screwing with firefox (just like bug 628331). If I run the firefox packaged by mozilla from firefox-3.6.12.tar.bz2 which (rumor has it) has its own cairo lib, the shredded text problem does not appear.
FYI: The xulrunner-1.9.2.13-5.fc14.x86_64 just added to updates-testing for bug 628331 does not fix this corrupted text issue.
Should be fixed on Fedora 15 and newer.