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I wanted to find the posts eligible for archaeologist badge and came across the following link
I clicked on the Login link and was shown a page as below
After clicking the Google Open Id provided, I was automatically logged in as the user jon.doe11019 instead of being prompted for my Google credentials or automatically picking my credentials that I had already used as seen in the above image.
OS : Windows 7 Professional 64-bit. Browser: Firefox 20.0.1