Integration in nextcloud: CODE puts menu into nextcloud menu bar, self-compiled not

(all done with the most recent versions)
when I use code from github, the collabora menu is integrated into the nextcloud menu bar:

when I use the version compiled from-source (no matter which one of the more recent versions), the nextcloud theming is hidden and the nextcloud … menu is not available:

This is easily reproducible on my test system: by switching between test/prod cool instances, this behaviour changes.
Which might be the place to influence this behavior?