@normandc Giiba is right your bank website is probably rederecting to another url pattern.
In order to check that you can have a look at the log file the error will be displayed.
Then you'll have to add another pattern with the webapp creator.
Thanks for your reply, at least that makes two of us trying to use Peertube. Out of a whole community. It's quite unfathomable to me. 😕
Anyway, not to sound ungrateful, I've been contributing to open source projects for the last 10+ years (not as dev but mostly documentation with close coordination with devs) so I think I know something about the other side of the fence. I like the UBports project, I want it to succeed, and I'm commited to using UT as my main device OS. Still, I am really confused by what I consider obvious blind spots, such as this one and a few others (the whole Telegram thing).
BTW I found a workaround about the full screen issue: in the address bar, change the /watch/ in the url for /embed/.