Watching Inflight Entertainment on MAC OS Ventura 13.5.2 (22G91) does not play videos

I cannot watch video on the United flights using the inflight entertainment.

I have even the United app installed (seems to be some browser based app)

But the inflight entertainment opens in the browser

Used Safari and Chrome

The video ads work, but when the video is supposed to start, nothing happens - no message, no error, no blocking pop-ups, simply nothing happens and the video frame where I just watched the ads remains empty.

On my iOS devise it worked fine, so it was not a problem with the service itself.

I checked security settings etc. - nothing obvious. Site rated as secure. No pop-ups blocked, cookies allowed, and so on...

I was hoping to find something to be installed from United, but there is nothing.

https://unitedprivatescreening.com/personal-devices

My MAC is within the supported devices according to the link above.

And the instructions give are...well, it did not work for me:

"Accessing personal device entertainment on laptops:

1. Open your browser and go to www.unitedwifi.com and select the entertainment tile.
2. Select a movie or TV show.
3. Click “Watch” and enjoy. "

Anyone with a suggestion?