Bionic-cloop: startprobleme nach Anmeldung

Servus,

wir hatten grade einen Ausfall bei der Anmeldung von ca. 15 min.
Ich habe nichts gemacht, die Systeme haben sich irgendwie erholt.
Was kann ich symptomatisch sagen: Man meldet sich an, er akzeptiert auch das PW aber er hängt im Hintergrundbildschirm fest, der DEsktop wird nicht gestartet

Sep 23 09:57:00 rl-pc05 gnome-shell[10552]: Enable Multi Monitors Add-On (v17)...
Sep 23 09:57:00 rl-pc05 gnome-shell[10552]: Add Monitors ...
Sep 23 09:57:00 rl-pc05 gnome-shell[10552]: pi:0
Sep 23 09:57:00 rl-pc05 gnome-shell[10552]: i:0 x:0 y:0 w:1920 h:1080
Sep 23 09:57:00 rl-pc05 gnome-software[10758]: no app for changed multi-monitors-add-on@spin83
Sep 23 09:57:00 rl-pc05 gnome-shell[10552]: Failed to add search provider /usr/share/gnome-shell/search-providers/nautilus-search-provider.ini: TypeError: appInfo is null
Sep 23 09:57:00 rl-pc05 gnome-shell[10552]: message repeated 3 times: [ Failed to add search provider /usr/share/gnome-shell/search-providers/nautilus-search-provider.ini: TypeError: appInfo is null]
Sep 23 09:57:00 rl-pc05 gnome-shell[10552]: Object St.BoxLayout (0x5568825c11c0), has been already deallocated - impossible to access it. This might be caused by the object having been destroyed from C code using something such as destroy(), dispose(), or remove() vfuncs
Sep 23 09:57:00 rl-pc05 org.gnome.Shell.desktop[10552]: == Stack trace for context 0x55688070f320 ==
Sep 23 09:57:00 rl-pc05 org.gnome.Shell.desktop[10552]: #0 0x7ffd10a0c8f0 b   resource:///org/gnome/shell/ui/popupMenu.js:726 (0x7fb3ead27340 @ 22)
Sep 23 09:57:00 rl-pc05 org.gnome.Shell.desktop[10552]: #1 0x7ffd10a0c960 I   resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7fb4040b5de0 @ 71)
Sep 23 09:57:00 rl-pc05 org.gnome.Shell.desktop[10552]: #2 0x7ffd10a0c960 I   resource:///org/gnome/shell/ui/popupMenu.js:744 (0x7fb3ead275e8 @ 23)
Sep 23 09:57:00 rl-pc05 org.gnome.Shell.desktop[10552]: #3 0x7ffd10a0c9c0 I   resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7fb4040b5de0 @ 71)
Sep 23 09:57:00 rl-pc05 org.gnome.Shell.desktop[10552]: #4 0x7ffd10a0ca60 b   /home/cache/kuechel/.local/share/gnome-shell/extensions/printers@linux-man.org/extension.js:105 (0x7fb3e8178450 @ 232)
Sep 23 09:57:00 rl-pc05 org.gnome.Shell.desktop[10552]: #5 0x7ffd10a0cac0 I   resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7fb4040b5de0 @ 71)
Sep 23 09:57:00 rl-pc05 org.gnome.Shell.desktop[10552]: #6 0x7ffd10a0d240 b   /home/cache/kuechel/.local/share/gnome-shell/extensions/printers@linux-man.org/extension.js:197 (0x7fb3e8178780 @ 94)
Sep 23 09:57:00 rl-pc05 org.gnome.Shell.desktop[10552]: #7 0x7ffd10a0d980 I   resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7fb4040b5de0 @ 71)
Sep 23 09:57:00 rl-pc05 org.gnome.Shell.desktop[10552]: #8 0x7ffd10a0da50 b   self-hosted:918 (0x7fb4040f12b8 @ 394)
Sep 23 09:57:00 rl-pc05 gnome-shell[10552]: clutter_container_get_children: assertion 'CLUTTER_IS_CONTAINER (container)' failed

ich werde natürlich testen, ob es an dieser einen Erweiterung „MultiMonitor Add-on“ liegt, die in meinem Image ist, aber nicht im original.

Diese Fehlermeldungen gehen immer so weiter, nicht immer diesselbe. Am Ende:

Sep 23 10:14:47 rl-pc05 gnome-shell[10552]: Object Meta.Background (0x556883ef9ca0), has been already deallocated - impossible to access it.
 This might be caused by the object having been destroyed from C code using something such as destroy(), dispose(), or remove() vfuncs
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: == Stack trace for context 0x55688070f320 ==
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: #0 0x7ffd10a09ab0 b   resource:///org/gnome/shell/ui/background.js:718 (0x7fb3ead0f4
d8 @ 22)
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: #1 0x7ffd10a0aa10 b   resource:///org/gnome/shell/ui/tweener.js:112 (0x7fb4040c8e68 
@ 37)
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: #2 0x7ffd10a0b980 b   resource:///org/gnome/gjs/modules/tweener/tweener.js:208 (0x7f
b4040d2b38 @ 54)
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: #3 0x7ffd10a0bad0 b   resource:///org/gnome/gjs/modules/tweener/tweener.js:337 (0x7f
b4040d2bc0 @ 1626)
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: #4 0x7ffd10a0bb80 b   resource:///org/gnome/gjs/modules/tweener/tweener.js:350 (0x7f
b4040d2c48 @ 100)
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: #5 0x556880ab4520 i   resource:///org/gnome/gjs/modules/tweener/tweener.js:365 (0x7f
b4040d2cd0 @ 10)
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: #6 0x7ffd10a0cf00 b   resource:///org/gnome/gjs/modules/signals.js:128 (0x7fb4040d22
30 @ 386)
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: #7 0x556880ab4490 i   resource:///org/gnome/shell/ui/tweener.js:244 (0x7fb4040cf808 
@ 159)
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: #8 0x7ffd10a0db50 I   resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7fb4040b5de
0 @ 71)
Sep 23 10:14:47 rl-pc05 org.gnome.Shell.desktop[10552]: #9 0x556880ab4410 i   resource:///org/gnome/shell/ui/tweener.js:219 (0x7fb4040cf780 
@ 15)
Sep 23 10:14:47 rl-pc05 gnome-shell[10552]: g_object_run_dispose: assertion 'G_IS_OBJECT (object)' failed

Dann ist alles wieder ok.
Das war aber zu dem Zeitpunkt nicht nur an dem Rechner so, sondern an mehreren neben an.
Das ganze dann nochmal ca. 11:45, wo es bei mehreren Rechnern hing, aber nicht bei allen mit diesem Stack trace.

Ich paste das jetzt mal als Erfahrungbericht, weder als Auftrag zur Fehlersuche, noch als Lösungsthread.
Mal sehn, ob noch jemand anderes Probleme findet.
Vg, Tobias