Footer Icon Option Disappearing

When I go to the customization settings for the footer, and click “Add new icon” it creates a field and flashes “font-awesome icon” breifly before disappearing, then it only allows me to input the title and link, but not any icon so it just appears blank. I used to have my icons up here but after i removed the existing icons and tried adding new ones it doesn’t let me choose an icon. Is there any way to fix this?

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