Created attachment 8729 
xsession-errors

This is a copy of the Ubuntu bug I created: https://bugs.launchpad.net/ubuntu/+source/xfwm4/+bug/1835622

"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"

Some additional notes:
- I had occasional crashed of xfwm or the panel, but those did not affect functionality
- Before the upgrade today I had no problems logging in to the Xfce Desktop
- Disabling the compositor in xfwm resolved the issue
- Else than the Xubuntu Staging PPA I also have: 
  * deb http://www.ui.com/downloads/unifi/debian stable ubiquiti
  * deb http://repo.mongodb.org/apt/ubuntu xenial/mongodb-org/3.4 multiverse  (I just saw the xenial here. Seems to be wrong. But probably not related to that bug here)


Those were the upgrades from today:

Start-Date: 2019-07-06  10:23:49
Commandline: /usr/sbin/synaptic
Requested-By: marting (1000)
Install: libllvm8:amd64 (1:8-3~ubuntu18.04.1, automatic), libllvm8:i386 (1:8-3~ubuntu18.04.1, automatic)
Upgrade: libthunarx-3-0:amd64 (1.8.7-0ubuntu1~18.04, 1.8.7-0ubuntu2~18.04), thunar-data:amd64 (1.8.7-0ubuntu1~18.04, 1.8.7-0ubuntu2~18.04), libegl1-mesa-dev:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libegl-mesa0:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libsystemd0:amd64 (237-3ubuntu10.23, 237-3ubuntu10.24), libsystemd0:i386 (237-3ubuntu10.23, 237-3ubuntu10.24), libglapi-mesa:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libglapi-mesa:i386 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), mesa-common-dev:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libxatracker2:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), udev:amd64 (237-3ubuntu10.23, 237-3ubuntu10.24), libegl1-mesa:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libreoffice-l10n-de:amd64 (1:6.0.7-0ubuntu0.18.04.4, 1:6.0.7-0ubuntu0.18.04.7), libudev1:amd64 (237-3ubuntu10.23, 237-3ubuntu10.24), libudev1:i386 (237-3ubuntu10.23, 237-3ubuntu10.24), libgbm1:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libreoffice-help-de:amd64 (1:6.0.7-0ubuntu0.18.04.4, 1:6.0.7-0ubuntu0.18.04.7), systemd-sysv:amd64 (237-3ubuntu10.23, 237-3ubuntu10.24), libwayland-egl1-mesa:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libgles2-mesa-dev:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libpam-systemd:amd64 (237-3ubuntu10.23, 237-3ubuntu10.24), systemd:amd64 (237-3ubuntu10.23, 237-3ubuntu10.24), thunar:amd64 (1.8.7-0ubuntu1~18.04, 1.8.7-0ubuntu2~18.04), libgl1-mesa-dev:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libgl1-mesa-dri:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libgl1-mesa-dri:i386 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libosmesa6:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libosmesa6:i386 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libnss-systemd:amd64 (237-3ubuntu10.23, 237-3ubuntu10.24), libgl1-mesa-glx:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libgl1-mesa-glx:i386 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), mesa-vdpau-drivers:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), mesa-vulkan-drivers:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libreoffice-help-en-us:amd64 (1:6.0.7-0ubuntu0.18.04.4, 1:6.0.7-0ubuntu0.18.04.7), mesa-va-drivers:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), docker.io:amd64 (18.09.5-0ubuntu1~18.04.2, 18.09.7-0ubuntu1~18.04.1), libglx-mesa0:amd64 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1), libglx-mesa0:i386 (18.2.8-0ubuntu0~18.04.2, 19.0.2-1ubuntu1.1~18.04.1)
End-Date: 2019-07-06  10:24:55