Oh, I hated it too, thanks to you I've found out it was just an animation setting and not a feature from the updates. Changed to animation "none" already. Thanks!
@dominmuda 1080p is 2K, when talking about TVs (2K, actually 1920, is the width, 1080 is the height), so I presume you mean 4K (3840x2160). Tried anything else at 4K yet? Perhaps your video hardware has trouble at such high reslution.
I this problem too It takes ages to load up a YouTube video and even when the page is actually loaded it takes another long while for the video to actually render. Then another while so it can render in HD. Same as you, its only on YouTube. The action delay while it loads is terrible as well, it takes 10 seconds for my clicks to register. It gets better after a bit of being on the video, but I still hate it.
On Windows, when Opera GX is open and playing media, you can open the Windows volume mixer and check that the Opera GX-specific volume is all the way up.
@leocg Thank you so much for replying, I just installed regular Opera, and it looks the same, I can't enable subtitles.
I found the answer in Reddit apparently I'm not the only one with this issue.
If anyone else comes across this problem, I solved by installing User-Agent Switcher and switching agents to Firefox-Windows in HBO.