Occasionally, font awesome icons do not display correctly. This appears to be when the values are loaded in CP1252 encoding rather than UTF-8, resulting in Mojibake like , ï˜ or ï„Œ.
This appears to be a bug in how Bubble assets are being served, in particular the run.css file is encoded incorrectly: you can see in this example run.css that there are rules like .fa-caret-down:before{content:""} (which should instead be .fa-caret-down:before{content:"\f0d7"} - see original font awesome 4.7.0 css)
Also see Icons displaying weird?