I just saw it in the newly migrated app, when entering a nonexisting url, the Django debug page is displayed, see: https://zpetnovazebnik.pyladies.cz/abc/
This shouldn't happen, given https://github.com/PyLadiesCZ/Zpetnovazebnik/blob/main/feedback/settings_production.py is applied. But is it?

ping @encukou who's got the access to production.