Fonts
Caffeinated comes with Google Fonts preloaded with the application. Simply search for a font by name and select it.
Alternatively if you have a font saved on your computer Casterlabs-Caffeinated can use that as well. Type its name in to the font box on the style screen of the alert you wish to use it on and Casterlabs-Caffeinated will find it and use it.
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If you install a new font while using Casterlabs-Caffeinated, you will need to restart the application in order for it to see the new font.