Consider dropping support for Mac OS 10.6, 10.7, and 10.8
Unless someone talks them out of it, Mozilla plans to drop support for Mac OS 10.6, 10.7 and 10.8 in Firefox 46, which means we will need to worry about this when we transition Tor Browser to the ESR 52 codebase. Read more here: https://groups.google.com/forum/#!topic/mozilla.dev.platform/gXZj0rQWEfI
We need to decide whether Tor Browser can and should continue to support those older versions of Mac OS.