Dear Xara...
Font Awesome's free collection, https://fontawesome.com/icons?d=gallery&m=free, is formidable.
It now has 1,513 Awesome Icons. It catalogues these in 75 categories.
You have far less: FA has 426 Brand Icons to your 170; you have selected 16 categories.
I happened to want a leaf and in searching AW and the OCC Symbols, I found the same Icon, but they were subtly different.
I can only assume you are sill using Font Awesome 4 Free and not moved to update to Font awesome 5 Free.
I assume the .OTF font files will need refreshing too.
FA's UI presentation also includes the Icon name. Seeing this allows for more meaningful searching. THE OCC Symbol should include this simple detail.
Acorn
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