Allow "muting" for sites added as an App

One of my favorite new features with the new Edge, is being able to add a web site as an App!  

I noticed if I add a site like Twitch or Mixer as as App, there is no place to mute the audio.  It would be nice if sites that use audio, and have been added as an Edge "app" would have the audio muting functionality in both the App's info/settings panel, as well as in the App title bar, similar to a the the browser tab.  

Thanks for your consideration!