Update: I found that File Provider Extension API is removed from Catalina features page. Is that mean this feature won't be available on macOS Catalina?
I upgraded Xcode to Xcode 11 GM2(11A420a) on macOS Catalina beta.8. Then I tried to create an application extension by clicking File > New > Target
and found that File Provider extension is missing from the application extension list for macOS.
I remembered I could create a File Provider extension for macOS in a previous beta version of Xcode 11. What to do now?