I can confirm the youtube issue. No idea if it might be some edge case with my distro or hardware. Forcing a GC collection helps but input events to the entire browser still feel laggy until I restart it. It's been going on for years now.
It occurs to me that it could be a pathological edge case triggered by ublock and youtube interacting. I'm not going to disable it to find out.
Go to about:processes and kill the YouTube process. All YouTube tabs and embeds will be marked as crashed, with a button to reload them. The memory leak will be reset and you won't have to restart the whole browser.
It occurs to me that it could be a pathological edge case triggered by ublock and youtube interacting. I'm not going to disable it to find out.