@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.
@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.