Required initializer unavailable in Mac Catalyst

Hello,

I've just enabled Mac Catalyst for my already available and working iPad.

When trying to build for Mac Catalyst I get this error in a subclass of NSURL. required initializer .... must be provided by subclass of NSURL

Ok. So I add that, but then it tells me the Mac Catalyst doesn't support NSPasteboard.

`NSPasteboard is unavailable in Mac Catalyst'

This seems like a catch-22!

I've tried variations like

#if canImport(AppKit) && !targetEnvironment(macCatalyst)
    required init?(pasteboardPropertyList propertyList: Any, ofType type: NSPasteboard.PasteboardType) {
        fatalError("init(pasteboardPropertyList:ofType:) has not been implemented")
    }
    #endif

But not having any luck.