Question about icon fonts

Hi WeWeb!
I have noticed that icons (from weweb library) on my page a loaded too slowly if internet is slow. As I understand its done through using an icon fonts?
If I use icons from all 4 available icon collection fonts does it mean that all 4 weweb icon fonts are preprendered on client side before my only 4-5 icons are show on the page?

If yes maybe i should generate a special icon font with only icons I use an upload it to fonts section so that decrease load time at the end?

Thanks in advance.