I did that. The entry (select * from oc_appconfig where appid = 'files_external';
) now looks like
| files_external | user_certificate_scan | []
But the warning
Es sind einige vom Benutzer importierte SSL-Zertifikate vorhanden, die von Nextcloud 21 nicht mehr verwendet werden. Sie können über den Befehl “occ security:certificates:import” in der Befehlszeile importiert werden. Ihre Pfade innerhalb des Datenverzeichnisses werden unten angezeigt.
still remains. The only thing that changes is that the bullet-list entry that was there pointing to the entry I removed from the json (?)-array is now gone.
As I understand the “warning” is nothing to be particular worried about but I like to have my admin-section as clean and free of warnings as possible.
Is there anything else I could try or did I do something wrong?
EDIT: I replaced the value ‘[]’ (an empty array) with NULL and now the warning is gone 