Although YouTube already allows you to switch between three player sizes: small, medium, and full screen. Sometimes it’s not enough, and you want more control over the player’s size.
The Chrome extension YouTube Resize lets you control the size of YouTube player to your liking with mucho ease.
How it works:
- Install the extension.
- Open a new tab with a YouTube video.
- Grab the right border of the video player with your mouse to change its size.
P.S. Use it in combination with Magic Actions for YouTube to get maximum control over the video player. (It’s especially useful for its auto-HD feature among other things)