Cause found: App formvox broke mimetypes for me. Disabled, it works again. Additionally, I had an incomplete list of mimetypes in db, fixed via occ maintenance:mimetype:update-db
comments
comment on
ALL files unscanned. ALL files without preview. ALL files download instead of rendering in browser
comment on
ALL files unscanned. ALL files without preview. ALL files download instead of rendering in browser
Turns out, the "unscanned" was just a tag from some app. I've remove those. But still the main issue remains: No picture has a thumbnail, all pictures download instead of rendering in browser