Recognizing Font Uninstall on visionOS

My visionOS app can install custom fonts.

My visionOS app also lists these fonts as available within the application, and I can see them in a list using CTFontManagerCopyAvailableFontFamilyNames

I manually track which fonts have been installed.

So far, so good. But here’s my problem: When a user uninstalls a font via Settings, I have no way to tell. That’s because CTFontManagerCopyAvailableFontFamilyNames will still list that font because it’s still available within the application.

How can I track these changes in my app when a font is uninstalled via Settings?

Recognizing Font Uninstall on visionOS
 
 
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