Reduce Browser's Energy Impact for playing YouTube Video
< Feedback on YouTube CPU Tamer by AnimationFrame
when I hover over the player
There is a specific fix for this problem in https://greasyforks.org/scripts/473972-youtube-js-engine-tamer
You are encouraged to install the script to fix the issue.
On a 180Hz monitor, YouTube by default peaks at 100% CPU usage on one core when I hover over the player, but this script fixed it and now the CPU usage is back to normal. Thanks a lot!!!