On two separate phones I can't play the videos in the screenshot area above the games. It just flashes and then fades back to a screenshot of the videos thumb...

Any one else experience this? Any ideas how to fix?

Is Youtube allowed in your area? If not, that might be the problem. Is your internet connection slow, because that's a potential problem as well. I'm not sure how much support GOG gives mobile devices, so that could be a problem as well.

Here is yet another idea: It might be requesting the wrong version of Youtube for your mobile. You know how there are both a mobile and a desktop version of Youtube and some mobiles, like mine, seem to have problems with picking the right one.

Apparently mobile internet connections in Thailand tend to be a lot slower than average, and this could affect your streaming of YouTube videos. Maybe google and find the fastest mobile net you can get; if affordable, it might help.

My source:
https://tech.thaivisa.com/turemove-dtac-ais-thailands-best-mobile-network-revealed/28436/

I just tested my tablet and the videos are playing fine. Then different browser than Chrome on my phones and the videos playing fine too.. I've cleared link defaults for Chrome, so must be clash with Chrome Android. How to report this?

Fixed now on chrome Android. Don't know if developers saw this and fixed or or just random.
EDIT: NOT FIXED, JUST WORKED ONCE AND THEN DONE

This is still happening to me on my phone (LG G6 ThinQ) using the chrome browser. Haven't tried any other browsers yet though...

Simply incredible. and not in a good way. 2019 and GOG still can't make videos work in mobile. 2008, okay, I understand. 2019 though? ugh.

GOG not ashamed? it's an issue that's been going on for more than half a year, which should have been fixed within minutes. Any 13-year old tech-savvy kid can insert a YouTube video into a web page and have it work properly.

But but GOG does not sell games for Android/iOS/(are there any others still around?).

People may browse the shop to see if there is anything interesting while on the train or some such. Buying from a mobile device should also work.

Try again holding your device in landscape position, this worked for me...

Thank you. Landscape worked for me too. This has been driving me crazy for ages.