Update webtop5 docs (#538)

Additional note for custom virtual hosts on Nextcloud

administrator-manual/en/webtop5.rst

@@ -423,6 +423,11 @@ A precompiled wizard will open:
    Remember to fill in the User name and Password fields related to access to the Nextcloud resource,
    otherwise it will not be possible to use the public link to the shared files
 
+.. note::
+
+If Nextcloud has been configured with a custom virtual host (eg. ``nextcloud.mydomain.com``) the :guilabel:`Path` must be changed from `/nextcloud/remote.php/webdav` to `/remote.php/webdav`, please note that `/nextcloud` prefix has been removed. Also make sure to enter the name of the custom virtual host inside the :guilabel:`Host` (eg. ``nextcloud.mydomain.com``).
+   Finally, remember to configure the virtual host name as server alias: access Server Manager Dashboard, click on the server FQDN and add a new alias inside the dialog.
+
 Proceed with the Next button until the Wizard is complete.
 
 Use the personal Cloud to send and receive documents