Thanks for the link to info I had already read and promptly forgotten about.
You're obviously correct about Ghostery's functioning client-side, but I questioned it because I get the place-marker on the page to which I originally linked, but not on
this page, despite the fact that disabling Ghostery makes the blocked content visible; I guess it's a function of the lack of ubiquity you mentioned. (Disqus is the culprit on my original linked Website.)
PS: I just realized that Ghostery's site-specific
unblocking works by clicking on the appropriate checkmark in its drop-down...not totally intuitive; I wonder why they didn't just use a third icon to accompany the existing two.
Edit: I obviously never watched the vid.