Re:Facebook detects if you are logged in Gmail
by kamkha on Saturday November 05, 2011 @10:12PM
(#3201575)
Did you happen to read the comments on the answers?
> Nope it's not that unfortunately. I tried it myself removing all linked accounts. The event above still happens.
Re:Facebook detects if you are logged in Gmail
by ceol on Saturday November 05, 2011 @10:37PM
(#3201637)
I was talking about this one: http://webapps.stackexchange.com/questions/20018/facebook-de...
"The OAuth tokens for Google are at https://accounts.google.com/b/0/IssuedAuthSubTokens (it's different from Linked Accounts).
When I tried it, Facebook created a popup with a OAuth prompt the first time and only briefly opened a blank popup on subsequent attempts. De-authorizing facebook makes the prompts appear again."
Unless they're talking about two different prompts?
Did you happen to read the answers? Two specifically mention that Facebook requests authentication access (OpenID, I believe) the first time. It appears this user authorized Facebook at some point in the past and forgot about it.
When I look at this page: https://accounts.google.com/b/0/IssuedAuthSubTokens I can see that at some point in the past, I allowed Facebook access to my Google Contacts (probably their "find friends" feature). Facebook could use that to check if you're logged in.