Logging out of Facebook does not do enough. It still retains cookies that specify your account ID even after you logout. You need to delete all of the Facebook

Logging out of Facebook does not do enough. It still retains cookies that specify your account ID even after you logout. You need to delete all of the Facebook cookies. Here is what cookies are retained, but you can test it for yourself to see. While logged in: datr, lu, openid_p, c_user, sct, xs and act act is your account number. now a new, fresh request after hitting logout still sends the following cookies: datr, openid_p, act, L, locale, lu, lsd, reg_fb_gate, reg_fb_ref If you do not delete cookies Facebook know and can track every user that has ever logged in at your computer.