Replace the Font Awesome 4 icons in your WoltLab Suite with the current and up-to-date version of Font Awesome 5 while being completely backwards compatible with the icon names of Font Awesome 4.
This plugin includes the free Font Awesome 5 icons, which have many more icons available than Font Awesome 4 had, with much done work to be an even better icon set than ever before. Check Font Awesome for more details.
After installation, you have nothing more to do. Font Awesome 5 is ready do go!