It ended up not working.
I didn't investigate it too much.
I just recreated the app and copied the database over.
@timconsidine i think that's because it remembers the password for the second time.
All topics are protected by default. This is a deviation from the ntfy default since we don't want unprotected instance. See https://docs.cloudron.io/apps/ntfy/#access-control . auth-default-access has to be changed .
https://docs.cloudron.io/apps/ntfy/#change-password for future readers.
@girish Now I can see it, too. Thanks! I'll give it a try.
Update: Works great. Tested with Element and Fedilab so far.