UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.119 Safari/537.36

Example URL:
www.youtube.com

Steps to reproduce the problem:
1. Open two youtube tabs with audio playing.
2. Right click and mute one tab.
3. Both tabs will have then been muted. 

What is the expected behavior?
Only the selected tab should mute. 

What went wrong?
Both tabs muted. Will mute any number of open tabs across multiple windows. 

Did this work before? Yes 63

Is it a problem with Flash or HTML5? HTML5

Does this work in other browsers? Yes

Chrome version: 64.0.3282.119  Channel: stable
OS Version: 10.0
Flash Version: Shockwave Flash 28.0 r0

Contents of chrome://gpu: