Just tried out this software, it's pretty awesome. However, I'm having some trouble with the thumbnails.
I can disable image_resize, then Thumbnails appear . The site also seems to load images that are natively smaller than "image_resize_dimension", whatever that may be, so my conclusion is that the actual resize operation is not working.
I do have a few errors in the diagnostic - can you tell me if these would cause the resize to fail, please? I've ostensibly installed php-mod-exif, but I can't figure out why it is not getting picked up. And I don't really need video previews, so I'm less concerned with the ffmpeg error.
Anything else I could check?