Nextcloud instance dead, OCC command not working anymore

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1

Nextcloud 19, Ubuntu 18.04, PHP 7.2

I have just enabled automatic updates of Ubuntu and automatic updates of Nextcloud apps.

Nextcloud is now not working anymore.
OCC command is not working anymore as well - how to fix it?

I would like to remove the app “Eml viewer” - how to uninstall it without OCC command?

Result of php occ:

PHP Fatal error:  Interface 'OCP\AppFramework\Bootstrap\IBootstrap' not found in /var/www/clients/client1/web2/web/apps/emlviewer/lib/AppInfo/Application.php on line 14

Result of tail -f nextcloud.log | jq

{
  "reqId": "psmkN7AfBJbPTdPpNYg1",
  "level": 3,
  "time": "2020-11-19T10:44:41+00:00",
  "remoteAddr": "",
  "user": "--",
  "app": "PHP",
  "method": "",
  "url": "--",
  "message": "Interface 'OCP\\AppFramework\\Bootstrap\\IBootstrap' not found at /var/www/clients/client1/web2/web/apps/emlviewer/lib/AppInfo/Application.php#14",
  "userAgent": "--",
  "version": "19.0.4.2"
}

Output of tail -f /var/log/apache2/error.log

[fcgid:warn] [pid 1360] [client XX.XX.XX.XX:63570] mod_fcgid: stderr: PHP Fatal error: Interface 'OCP\\AppFramework\\Bootstrap\\IBootstrap' not found in /var/www/clients/client1/web2/web/apps/emlviewer/lib/AppInfo/Application.php on line 14

Thank you!

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