Do you think it's creepy that others on Facebook are able to see when you've seen their messages? This browser plugin should put your mind at ease.
The "read receipt" feature in Facebook messages (and other chat clients) can be useful if, say, you want to be sure that your message got where it's going, or that the other person is responding in good time. But for some, the "Seen by..." alert seems like a bit too much information. And since Facebook doesn't let you turn the feature off, those people may be looking for other methods to circumvent it.
A new Web browser plugin from Crossrider called Chat Undetected prevents Facebook from detecting that you have seen or read a message, and consequently from reporting to the other person that you have done so. They'll still be able to see if you're online, though.
If you're on the other side of the fence and want to see what Facebook has hidden from you, try this other tool that surfaced today that lets you see who has unfriended you.
Chat Undetected is a quick install and works on Chrome, Firefox, Internet Explorer and Safari; you can download it here, although the server seems to be under heavy load at the moment.
Keep in mind that Facebook just rolled out some new messaging features today, so you may wish to put off installing this for a few days while the developers catch up and work on any bugs or incompatible services.
Devin Coldewey is acontributing writer for NBC News Digital. His personal website iscoldewey.cc.