YouTube High Definition от Baris Derin

YouTube High Definition solves a number of annoying YouTube issues.

Features

Automatically play all YouTube videos in the highest resolution possible

Specify your preferred resolution (4k, 1440p,1080p, 720p, 480p, 360p, 240p, 144p)

Change video player size

Control auto-mute volume and auto-stop video play

Supports HD play when videos are embedded in external sites like Facebook, Twitter, Reddit, and others

Set a preferred volume level for all videos

Improve music on YouTube by always playing the best sound quality automatically