Not the parent, but Safari on iOS. https://caniuse.com/webm

I just added .mp4 fallbacks, thanks for the tip!

For me the videos look like images, both on Firefox and chromium on linux.

No play button is displayed, no video playback control bar either, and pressing on space bar does not start the video. Right-clicking over the video shows a context menu with "play" option.

It is confusing to see these as screenshots of the cluttered interface and no indication that these are videos.

Do the videos auto-play for you when they appear?

I made the bad decision of hand-coding the landing page in React, this is the result of it :)

I think they have autoplay disabled, I have autoplay disabled as well and have the same experience. If I enable autoplay it works. (Firefox)