Adding San Francisco Mono to Font Book
Apple introduced a new fixed width font in Xcode 8 — San Francisco Mono — but they’ve not made it available for system-wide usage.
If you want to make the fonts available for system-wide usage, you need to extract them from the Xcode 8 beta and add them to Font Book.
Assuming Xcode is installed in
/Applications, navigate to the below folder using Finder:
Then select the fonts in that folder and drag them to Font Book.