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This script enhances the user experience when pausing a YouTube video in full-screen mode by hiding certain elements and adding a play icon.
< YouTube Fullscreen Enhancerについてのフィードバック
I implemented this feature, and you can install the script v0.1.1. I felt that this feature wasn't very good, so I removed it from the code.
Thanks for the reply, actually I found a better Google extension yesterday to implement these features：https://chromewebstore.google.com/detail/youtube-controller-hidden/kclpkcemkhniandfingdpopdgcjlgcld
Function request: Keep the Hide Player Control Bar and Hide Video Title when the mouse moves