title: RequireNonce is true (default) but validationContext.Nonce is null
body: <p>I have an app running in azure using Azure active directory.  Some of the users have just reported getting this error trying to access the app.  I can access it ok, so can many other users, its only certain users that are having the issue, heres the error message  </p>
  
  <p>IDX10311: RequireNonce is true (default) but validationContext.Nonce is null. A Nonce cannot be validated.  If you dont need to check the nonce, set OpenIdConnectProtocolValidator.RequireNonce to false</p>
  
  <p>Ive googled it but I cant find a solution, has anyone else experienced this problem ?  How Can I fix it ?</p>