I have also tested the tarball releases from https://www.mozilla.org/firefox/
The problems are identical with those releases. I tested 94.0.2, 95.0, 96.0b2 and 97.0a1. I ran all of them with `MOZ_ENABLE_WAYLAND=1`. 94.0.2 works perfectly fine, and all the other releases show lag while scrolling, and the GNOME Shell / Mutter process even seems to lock up when Firefox starts a download, prior to the "Save file" popup window. When run on Xwayland (without the environment variable), all releases run fine. So "something" has changed between 94.0.2 and 95.0, breaking the Wayland backend at least on gen4 Intel graphics. My only other devices are Pinebook Pro's, using the Panfrost driver. I don't seem to be able to reproduce this on there. But those are arm64 builds, so maybe not the best comparison. -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to firefox in Ubuntu. https://bugs.launchpad.net/bugs/1953685 Title: [Regression] Firefox 95 is laggy on GMA X4500 (EGL related?) Status in firefox package in Ubuntu: New Bug description: I have a couple of ThinkPads with old Intel GMA X4500 graphics. Since the update to Firefox 95, it's been verry laggy; especially noticeable while scrolling, for instance on about:support. Strangely, the bug is less present when the browser window is smaller. A maximized window lags very badly, but when resizing the window to under ~75% of the screen, it becomes a lot better. I have tried completely clean profiles by renaming ~/snap/firefox, but this made no difference. I have a feeling that EGL has something to do with it. When I force the Firefox snap to run on Xwayland by running `WAYLAND_DISABLE=1 snap run firefox`, the bug is *not* present. When I run the Firefox 95 deb (from jammy) on Wayland, by running `MOZ_ENABLE_WAYLAND=1 firefox`, the bug is also present. (When I run the deb without that environment variable, it falls back to Xwayland, which works normally.) However, when I set gfx.x11-egl.force-enabled to true in about:config, it also lags. One may assume that EGL is simply broken on this chipset, but that is not the case. When I run the Firefox *94* deb (from focal) with `MOZ_ENABLE_WAYLAND=1`, it works fine. Also, when I run `snap revert firefox` to go back to 94.0.2-2, the bug is not present, even when running on Wayland, using EGL. I have tested the snap both on focal and jammy on the same hardware. The bug is identical in both cases. tl;dr: On old Intel graphics Firefox 94 was working well with GLX and EGL, while EGL seems broken on Firefox 95. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1953685/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
