Mutex is a Chrome extension that lets you control which tabs are audible and visible from your phone! It ensures you'll only hear audio from one tab at a time. For instance, you can easily switch to a different game during a commercial break with just one tap.
Installing a desktop app, Mutex Turbo, enables Mutex to switch between tabs while remaining in fullscreen mode.
Mutex is currently in development and is not yet stable. You can install Mutex here.