Love Ghostery. In Ver. 7.1.1.5 (and versions from November 2016 to this ver.), if 'Accept cookies from sites' option is not checked in Firefox v.50.1.0 (and the prior version), Options, Privacy section, even if they are accepted for just that page, the Ghostery trackers do not appear. It was as difficult figuring out this bug over the last two months as solving Will Shortz Sunday Puzzle on NPR. I have to rest now... I'm exhausted.