By the way, I opened an issue for MinIO here: https://github.com/minio/minio/issues/21694
It would be great if MinIO could properly show previews for .webm videos as well.
When I store the same recording in a normal folder in Cloudron, the video preview works correctly.
However, when the file is stored in MinIO storage, the preview does not work.
It looks like the MIME type is not detected correctly, which causes the video tag to use:
type="video/mp4"
even though the file is actually a .webm.
This prevents browsers from playing the video.
Proper support for serving .webm with Content-Type: video/webm would fix the issue.