Also verified fixed in mantic using version 45.2-0ubuntu2~really45.0 and the test case that's now in the Bug Description above.
** Description changed: [ Impact ] There is heavy stuttering visible in Firefox with mutter 45.1/45.2 when kinetic scrolling a non-animated web page with a touchpad. This is a regression introduced upstream in mutter 45.1 (8f27ebf8). [ Test Plan ] 0. Find a laptop with a touchpad. 1. Open a simple web page like a Wikipedia page in Firefox. 2. Use two fingers on the touchpad to fling it so it continues scrolling. Expect: The scrolling proceeds and slows perfectly smoothly. [ Where problems could occur ] Anywhere in frame scheduling (visual smoothness), since that is the code affected. [ Other Info ] - Since the bug only hurts the triple buffering patch, that's where it has - been fixed upstream: + The bug was introduced upstream in 45.1 by + https://gitlab.gnome.org/GNOME/mutter/-/commit/8f27ebf87eee6057992a90560d4118ab7bdf138d + but since it only hurts the triple buffering patch, that's where it has + been fixed: https://gitlab.gnome.org/Community/Ubuntu/mutter/-/commit/0b896518b2028d9c4d6ea44806d093fd33793689 https://gitlab.gnome.org/Community/Ubuntu/mutter/-/commits/triple-buffering-v4-45 [ Workaround ] In /etc/environment: MUTTER_DEBUG_TRIPLE_BUFFERING=always or "never" also works. Just not "auto". -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to mutter in Ubuntu. https://bugs.launchpad.net/bugs/2046360 Title: Heavy stuttering in Firefox with mutter 45.1/45.2 Status in mutter package in Ubuntu: New Status in mutter source package in Mantic: Fix Committed Bug description: [ Impact ] There is heavy stuttering visible in Firefox with mutter 45.1/45.2 when kinetic scrolling a non-animated web page with a touchpad. This is a regression introduced upstream in mutter 45.1 (8f27ebf8). [ Test Plan ] 0. Find a laptop with a touchpad. 1. Open a simple web page like a Wikipedia page in Firefox. 2. Use two fingers on the touchpad to fling it so it continues scrolling. Expect: The scrolling proceeds and slows perfectly smoothly. [ Where problems could occur ] Anywhere in frame scheduling (visual smoothness), since that is the code affected. [ Other Info ] The bug was introduced upstream in 45.1 by https://gitlab.gnome.org/GNOME/mutter/-/commit/8f27ebf87eee6057992a90560d4118ab7bdf138d but since it only hurts the triple buffering patch, that's where it has been fixed: https://gitlab.gnome.org/Community/Ubuntu/mutter/-/commit/0b896518b2028d9c4d6ea44806d093fd33793689 https://gitlab.gnome.org/Community/Ubuntu/mutter/-/commits/triple-buffering-v4-45 [ Workaround ] In /etc/environment: MUTTER_DEBUG_TRIPLE_BUFFERING=always or "never" also works. Just not "auto". To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/mutter/+bug/2046360/+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