Leaves a big black void on the right side of the video where chat window usually is. Chat window/the black void can't be hidden while this extension is enabled. This is worse than just manually closing the chat without this extension.

A musthave addon. Hides annoying chat window. Also comments - by default. All is optional.

I installed it. Refreshed the page. Comments & chat are still there. I wish there was a 0 star option. Don't bother with this...