Facebook is the best place to hangout with friends even if Google plus have a hangout option in it , if you are not in Google plus you can get an invitation to Google plus from here . The looks of chat box has changed since Facebook enabled the Video calling option and it no longer shows friends by list making it difficult to go invisible with single click. So to go offline to a specific group of people you have to create a group with them in it ( you can do it from here ). once you have created the group say invisible click on the chat box then the flower like icon (small gear icon) located at the bottom of the chat box, then there will be an option to Limit Availability.. Once you click the Limit Availability option a pop-up window comes out with a list of Groups you have created. Put a check mark on the Groups from which you want to stay invisible and click Okay note that there is another option on the top saying " Make me u...
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