YouTube is lagging in fullscreen mode


Description of the issue: YouTube fullscreen videos are lagging (dropping frames), whether in 720p, 1080p or higher with the framerate of 60. When I press Alt+Tab and switch to show another window, the video playbacks perfectly fine and with the same quality.

Exact URL of the website in question: https://www.youtube.com/

Did the issue present with [default Shields settings]? yes

Does the site function as expected when Shields are turned off? no

Is there a specific Shields configuration that causes the site to break? If so, tell us that configuration. no

Does the site work as expected when using Chrome? yes

**Brave version (check About Brave): V1.18.77

PS: Better understanding in this video: https://www.youtube.com/watch?v=nI3Rf0Mv-Ik

I found a fix. I tried disabling FreeSync from the GPU driver and now it’s working fine.