Karel on Nostr: OK, so the worst case happened :). On some clients the video appears and works ...

OK, so the worst case happened :). On some clients the video appears and works (Nostrudel). On some clients it only appears but does not work (iris.to) and on some clients it does not appear at all (plebstr). Any advice what should I do better to make it work everywhere? Change format? Upload it somewhere else? I just uploaded it into my wordpress site and copied the URL.