I have found out IPB uses the cdnjs library but the problem is that the web fonts of that library haven't been updated to 5.0.0 yet they're still in 4.7.0.
https://cdnjs.com/libraries/font-awesome
IP.Board Support
Installing FontAwesome 5.0.3 on IPB
Submitted by 410, 20-03-2018, 01:49 PM, Thread ID: 80845
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