Don't you wish you could go on Facebook and nobody would know that you are there. In your account in your messenger, click on the three dot menu. Then click on Turn Off Active Status.
In the next box, I selected Turn off active status for all contacts. Then OK.
And that's it. Do this for all your devices you use Facebook on to be effective. So it seems to be device oriented. I'm not sure how well this works. It says in the information box that I should still be able to see my friend's activity but when I checked my contacts list; it was grayed out with no activity indication from anybody.
I beginning to either think Facebook has this option backwards or I don't think it does what it supposed to do. I was thinking Nija stealth mode and you couldn't see me coming until it was too late. :-) So, have you used this and what where your results?