I have many errors coming from FBSDK when running Xcode 12 that I would not get any on Xcode 11.
Duplicate interface definition for class 'FBSDKGraphRequestConnection' Property has a previous declaration No type or protocol named 'FBSDKCopying' Reference to 'FBSDKCopying' is ambiguous Duplicate interface definition for class 'FBSDKAccessToken'
I had FBSDK 7.1.1 then I updated to FBSDK 8.0 and it solved the issue.