@jasonekratz @adamprocter thankyou both.
This all started with trying to get a video to play in-line on the web page. Overcast creates an .mov .. which silly me just uploaded, wrote the script and it failed to display at all.
Exploring more, the script ‘didn’t support’ .mov .. needed to provide an mp4.
First time round I found a web site that did the conversion … pretty easy … and worked.
Next time round I found a setapp app which likewise did the conversion … again, pretty easy … and worked.
But still seemed to be a step too many for something so simple.
So. Looked further. Found a comment that if you just change the extension it will work. I tried that. It worked.
Definitely the easiest solution. I guess I just wonder why mov can’t just be supported? So far, no good reason.