You may try to add
'allow_local_remote_servers' => true,
to /usr/share/nextcloud/config/config.php
See also Nextcloud - Remove Collabora and Install OnlyOffice - #4 by mrmarkuz
You may try to add
'allow_local_remote_servers' => true,
to /usr/share/nextcloud/config/config.php
See also Nextcloud - Remove Collabora and Install OnlyOffice - #4 by mrmarkuz