2-6 in 48 hours.
11:26 pm — Monday, 13 March 2017
It depends on the context. You want them (muted) in feeds like Twitter and Facebook. But not in places where you don't expect them, especially with audio, such as loading a page you thought was an article.
3:02 pm — Tuesday, 14 March 2017
Apple needs a block for this in Safari in the same way they let you block sound in the active window, and any other open window.

I enabled the Safari Developer Tools block this article mentions a few months back. It's nice, but it remains a little sloppy.
4:14 pm — Tuesday, 14 March 2017
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