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However, at around the time the new features began appearing (4:15 ET, 00:25 East African Time), the site went down for many users, including all of us here at PC Tech. As expected, hundreds of users have since turned to Twitter to complain about the outage.

At that time, source close to Facebook said the outage was related to an issue with customized tabs on Facebook Pages, which disappeared an hour before the site went down. In addition, Page owners were unable to determine which tab visitors landed on. When the site reappeared temporarily, customized tabs and landing pages were restored.