Add a custom icon in addition to Default and Awesome Font libraries

Dears, how are you?

I would like to add a custom icon in addition to the ones in the Default and Font Awesome libraries.
Like the icons created through fontello, for example. I’ve already managed to insert custom icons to WordPress and use them in Elementor, but I can’t select these icons when selecting icons, from the cart, for example.

Thanks in advance!

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