@erodingerod Same happening to me in Opera GX I have a playlist with over 700 songs and the entire tab only the tab of youtube is really slow can't barely even navegate throught it.

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.