While this is an impressive 'demo' feature, it is designed in a very limited way as it requires SQL db as backend support even when the three underlying membership/role/profile use Azure Storage(and thus other in the cloud storage as well), the OpenAuth namespace is hard coded to use EF and must use SQL equvialent(then there are hardcoded connection string name in the assembly which is entry level programmer mistake).
Try to use this feature on Azure(the generated template anyway) and you would know what I mean. Another case of the left hand don't know what right hand is doing in the huge Microsoft organization.
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