Unicode chars in status are not printable

[feistiny]

Hi!, this is a great repo. I have been watched for a long time. Recently I started using i3wm. I tried to use your whole configuration, but sth not work, such as the unicode char 0xf073 doest show correctly in the status bar, neither in vim or terminal, while I searched that shows it is in a private user area, So how do you make it work, or I missed sth.