Facebook took the chat down for maintenance moments after a Facebook chat security hole was identified that allowed users to view live chats and pending friend requests of their Facebook friends. While chat is down for maintenance for more than an hour, you can still use third party clients like AOL an Pidgin to use Facebook chat. See our complete guides to use Facebook chat on third party clients:
As long as the Facebook Chat on website is concerned, we are not sure when it will go back online.
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