Comment 14 for bug 740631

FWIW, the cross itself makes it look garbled for me, at least in the initial impression. Only after a second or two I realized that it was envelope with a line over it. For me, it'd work better if it had no cross over (red is 'negative' already), though I agree that'd be harmful for colour blind users.

As to ideas on how could we improve them, I definitely agree it's a hard problem, especially for the unmute action (negative of an already negative action, sounds like fun, since it's not really a positive action, which would be "subscribing"). Perhaps the mute action could instead take the shape of a hexagon resembling the "Stop" sign with the envelope in the middle? Not saying it'd be possible to fit it in 14px.