ASPresentationAnchor opens two instances of Safari on Big Sur

Using ASWebAuthenticationSession and ASPresentationAnchor for OAuth has been working as expected but after updating to Big Sur the authentication flow is now opening two Safari windows. This occurs only when Safari is completely shutdown, when an instance is running a single window will be displayed as expected.

Microsoft has an example which is having the same issue. https://github.com/Azure-Samples/ms-identity-macOS-swift-objc

Has anyone else come across this with Big Sur?
I have the opposite experience: ASWebAuthenticationSession works as great on macOS Big Sur 11.2.3 but opens two windows on macOS Catalina 10.15.7. At least it looks like a bug in ASWebAuthenticationSession and not a programming error on our side.
ASPresentationAnchor opens two instances of Safari on Big Sur
 
 
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