Focused StackExchange — Eric Xing

Tired of the default StackExchange/StackOverflow wasting precious real estate, but don't want to hide the sidebars? This extension will provide a more responsive design than the traditional layout! Say goodbye to the clutter and hello to Focused StackExchange.

Features:
- Sacrifice nothing: Minimizes the sidebars when not relevant, automatically show them when the mouse is over them
- Compatible with CSS styles of most SE communities
- Compatible with other extensions that change the theme (ie DarkReader)
- It's fast as hell. You won't even notice it loading
- It's free and open source

demo:
https://i.imgur.com/RbWVfOR.gifv