UserAgent: Mozilla/5.0 (Windows NT 6.1; rv:45.0) Gecko/20100101 Firefox/45.0

Steps to reproduce the problem:
Latest Chrome on Windows 7 x64.

You have a very useful feature that has been hidden for a long while. It allows muting a tab when it is playing audio. This is very useful because some websites have very annoying audio. Unfortunately this flag is not enabled by default, and must be found on a flags page where it is named 'Tab audio muting UI control'.

What is the expected behavior?

What went wrong?
Firefox already has this by default. It is the intuitive response to click the speaker and have it mute. Chrome should turn on this option by default for everyone.

Did this work before? N/A 

Chrome version: <Copy from: 'about:version'>  Channel: n/a
OS Version: 6.1 (Windows 7, Windows Server 2008 R2)
Flash Version: Shockwave Flash 24.0 r0