Early this morning (30 October UTC +8) our engineers were alerted to the situation where users were not able to log into VSocial via Facebook Connect.
Facebook returned an error similar to below:
This affected all logins to VSocial.
Our engineers were able to pinpoint the cause: Facebook made a small change to the login mechanism as part of their weekly release that affected the authentication module of VSocial. Our engineers resolve the issue and logins are now working.