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I can't believe it's still a thing; I've encountered this error repeatedly since the release of Windows Identity Foundation and have just encountered it again with Azure AD and MVC.  You just have to add this somewhere before using an AntiForgeryToken in MVC:-

AntiForgeryConfig.UniqueClaimTypeIdentifier = "";

To get past the error:-

A claim of type '' or '' was not present on the provided ClaimsIdentity.