The simpler media website CMS
as I can see there https://www.zenphoto.org/news/features/#manage-image-video-and-audio-files, mp4 video files are supposed to be supported by zenphoto.
so, I uploaded a mp4 file but there there is wrong thumbnail for it:
you can here: https://test.vincentbourganel.fr/images/illustrations/
can you help me?
ps: I have the issue with mp3 files and text files