@Timo: I could not test this earlier because I was on holidays. So finally here are the results:
1. (If I understand correctly the fix from bug 1836721 is already in bionic-updates) I upgraded all packages, but the bug still persists (error message "xfwm4: ../src/mesa/drivers/dri/i965/intel_mipmap_tree.c:1285: intel_miptree_match_image: Assertion `image->TexObject->Target == mt->target' failed.") 2. So I enabled ppa:ubuntu-x-swat/updates and upgraded all packages, but the error still persists. >From my point of view it seems this bug is not fixed by bug 1836721. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to mesa in Ubuntu. https://bugs.launchpad.net/bugs/1835622 Title: Cannot start desktop session with compositor enabled Status in Xfwm4: Invalid Status in mesa package in Ubuntu: New Status in xfwm4 package in Ubuntu: Invalid Bug description: I cannot login to the Xfce desktop session anymore. in ~/.xsession- errors there's the message: xfwm4: ../src/mesa/drivers/dri/i965/intel_mipmap_tree.c:1285: intel_miptree_match_image: Assertion `image->TexObject->Target == mt->target' failed. Earlier today Mesa was upgraded via bionic-updates from 18.2 to 19.0. I'm running Xubuntu 18.04 and I'm also using the Xubuntu Staging PPA with xfwm4 4.13.3 To manage notifications about this bug go to: https://bugs.launchpad.net/xfwm4/+bug/1835622/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp