Note that in @cstine's answer above, there's a stray back-tick (aka grave accent mark) at the end of the line of code. If you paste that character into the Code Injection box it can cause problems. Here's the code without that character for easy copy-pasta:
<link href="//maxcdn.bootstrapcdn.com/font-awesome/4.2.0/css/font-awesome.min.css" rel="stylesheet">
I've also found that you can change the 4.2.0 numbers to a newer version of Font Awesome to access the new icons. E.G.:
<link href="//maxcdn.bootstrapcdn.com/font-awesome/4.4.0/css/font-awesome.min.css" rel="stylesheet">
or
<link href="//maxcdn.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet">
CaseyH1570048191 got a reaction from samkeen in Can I use Font Awesome?
