MakeUseOf.com has some great tutorials on how to hack your Facebook accounts with javascript code and GreaseMonkey. These hacks won’t let you actually “hack” a facebook account itself but lets you do some really fun things like this one we did last time.
Change chat status to invisible:
javascript:statusControl.sendVisibility(false);
Change chat status to visible:
javascript:statusControl.sendVisibility(true);
Close all chat windows with person 1122334455:
javascript:chatDisplay.tabs[1122334455].tabXOnClick();
Open application tab:
javascript:applicationDock.toggleTab();
Bring up notifications:
javascript:presence.toggleTab('chat_status_control','chat_status_control_tab');
Bring up friends list:
javascript:buddyList.toggleTab();

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