> which has removed the possibility of disabling webrender I assume you already tried the newest graphics drivers.
Why would you want to *completely * disable WebRender? Do hardware AND software WebRender crash for you? You can set gfx.webrender.software to true to disable hardware WebRender and enable software WebRender instead. Please try this instead of using an e-mail client with security vulnerabities (since Thunderbird 91 won't receive any further security update we have to assume that Thunderbird 91 is insecure now). -- 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