Cannot obtain third-party custom fonts correctly

Preconditions:
The certificate has been opened to obtain third-party fonts
2, Use Installed Fonts is checked in Capabilities

Problem scenario:
In iOS/iPadOS 13 or later, after successfully installing custom fonts through third-party apps. Open your own APP through [UIFont familyNames] or CTFontManagerCopyAvailablePostScriptNames() Corresponding font data is not obtained.

difference:
The above questions can be correctly obtained in the following scenarios
  1. In the native software Apple Pages, it can be obtained normally

  2. In the same APP, get the font by using UIFontPickerViewController and select it for use. After that, you can get it through [UIFont familyNames] or CTFontManagerCopyAvailablePostScriptNames() normally, and the overwrite installation is also normal (the uninstall installation is gone).

anyone here?
Cannot obtain third-party custom fonts correctly
 
 
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