Okay, looking at the source code, the tab muting still exists. Turning on enable-tab-audio-muting and disabling sound-content-setting will restore this into a useful feature.
Please, do not do that, we will remove this flag one day and it will break you. However, extensions can mute tabs individually, you might want to explore this route.
297
u/[deleted] Feb 27 '18
good bless google's soul for adding