From some time (I'd say from January but I can't be sure) when I switch tabs I see images from old pages I've visited briefly flicker before the actual tab content appears. These pages are not anymore open, and often I visited them more than 1 hour before (I'd expect those images to be GCed), and I've visited far more pages after them (I'd expect those images to be out of the cache). This seems to happen particularly often when I open twitter pages that have a background image (for example http://twitter.com/guildwars2/). Unfortunately I cannot reproduce reliably, so it is hard to both get a clue on what is causing it and a regression range :( (setting as unconfirmed due to this) Regarding addons I have dominspector, adblock plus and bugzilla tweaks. I'm using D3D9 layers (nVidia 7900 GS).
hm I have to correct this a bit, I'm pretty sure I've just seen about:home flickering when switching between bugzilla tabs, clearly about:home is not open. So probably not related to backgrounds, but pages with large colored backgrounds are more noticeable.
I can confirm this behavior. Sometimes I saw a very short flickering when I switch tabs (only in content area). That include rendering a page that contain a part of: closed page (background), flash plugin (like Youtube video player content), or images (layer) that should be (?) discarded a long time ago. Also sometimes when I unmaximize browser window and grab right browser border and very fast resize window, I can see under a recent tab (rendered page) a layer with content that should be discarded. Often after these layers is present few switch tabs later it is a chance that he flicker between switching unrelated tabs. It happens sometimes, but i don't have a good steps to reproduce else than: open a lot of tabs, close some of them and just switch between others. My computer configuration is also affected by Bug 626352 . But due to landing Bug 611698 , my driver is blacklisted (Ati/AMD probably never release new drivers for my graphic card, and then I can't check that this is a graphic card driver failure. But I see that this behavior is reproducible on some older ATI/AMD (RADEON X1300) and nVidia (7900 GS) card..) and by default Firefox is configured to work without hardware accelerated layers. Of course I can force acceleration on (layers.acceleration.force-enabled;true in about:config) but then, when I switch the tabs, look into line 1 of this comment. I am probably just out of luck, no hardware accelerated browser (without bug) until: I buy newer laptop :) or I can convince himself that flickering is good to my eyes (right now I have acceleration switched on - flickering happen sometimes), or bugs when switching tabs will be workarounded in Firefox (try first find a one developer who could even once reproduce this bug) or Chrome/Opera will have different "magic" implementation of hardware acceleration... Windows 7 32bit, layers.acceleration.force-enabled;true in about:config, 1/1 Direct3D 9, ATI MOBILITY RADEON X1300, direct 2d: off, DirectWrite: off.
(In addition to comment #2) > > Also sometimes when I unmaximize browser window and grab right browser border > and very fast resize window, I can see under a recent tab (rendered page) a > layer with content that should be discarded. Often after these layers is > present few switch tabs later it is a chance that he flicker between switching > unrelated tabs. > Check the recorded video from past builds, sometimes I saw when browser window was resized, a content from closed tab (in area where was a glitches in video): http://www.youtube.com/watch?v=x7UaA9cC580 > > But due to landing Bug 611698 , my driver is blacklisted > My mistake, should be Bug 623338 - Block all old drivers for ATI, NVIDIA, and only whitelist the big three, to control risk
Created attachment 513241 [details] Recorded video of remaining layer after closing tab and resizing browser window See comment 2 and 3 for more details 1/1 Direct3D 9 Mozilla/5.0 (Windows NT 6.1; rv:2.0b12pre) Gecko/20110216 Firefox/4.0b12pre
Marco, kolubinowicki, do you still see this?
Probably it could be closed (there were many video glitches when introducing hardware acceleration to Firefox). As I am not seen the glitches from the bug anymore, after landing bug: https://bugzilla.mozilla.org/show_bug.cgi?id=623338