I am also seeing the same behaviour. Previously I just disabled the WebRender as well (since that made the difference in being not laggy), just to make Thunderbird useable. Here is my profile when moving the mouse over the messages: https://share.firefox.dev/3CCIknA
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to thunderbird in Ubuntu. https://bugs.launchpad.net/bugs/1959747 Title: [upstream] Very high CPU and slow responsiveness in Thunderbird 91 Status in Mozilla Thunderbird: Confirmed Status in thunderbird package in Ubuntu: Triaged Bug description: Very high CPU and slow responsiveness in Thunderbird 91.5.0. Just moving the mouse cursor over a message list results in 365% CPU for me. I had to set this in the config editor to fix it: gfx.webrender.force-disabled = TRUE Upstream bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1730423 To manage notifications about this bug go to: https://bugs.launchpad.net/thunderbird/+bug/1959747/+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
