Collectives behind SSL Terminating reverse proxy not working (redirects https -> http)
A Nextcloud (Version 24.0.6) is running behind an SSL terminating reverse proxy (Traefik), so internal traffic (Traefik -> Nextcloud) is running with HTTP. To the outside Nextcloud is just reachable via https through the mentioned reverse proxy at a subdomain (https://cloud.my.domain). Nextcloud and each and every installed app (News, Deck, Office, Contacts, Circles, Cookbook...) are working fine; when clicking at the menu icons the apps open. But when clicking on the menu icon of the freshly installed Collectives App, it redirects to http... and so is not reachable:
(Notice the URL of the menu icon is correct https://....) (Notice the 301 redirect to http://...)
When I manually correct the URL to https://... Collectives works normal.
While doing the screenshot I noticed, that the menu link goes to:
https://cloud.my.domain/apps/collectives
The redirect URL is: http://cloud.my.domain/apps/collectives/
Notice the trailing slash.... could this have sth. to do with this behaviour? But why doesn't it correctly redirect to https at all?
BTW: For testing I even made a "overwriteprotocol=>'https'" entry in nextclouds config.php but this didn't help.
Any hint? Thx in advance