In a shared link with photos, only thumbnail - no photo after clicking it

NC 18.0.1

in NC 17.xx I had gallery. it was shared (some folders) and could be seen read only. also can click and open the picture.

Actual situation:
now on NC18.0.1
gallery is not tested and has been disabled automatically.
Photo is the new gallery.
Shared a photo folder read only: now only thumbnails can be seen. When clicking it… white screen and than back to the list!

Any one any idea what is happening?

no one with that issue?
Any chance that photo is broken when anonymously (read only) shared?

really? no one