You probably know this, but not all Opt-out cookies turn out to be consensual. Is it possible to review a list of just such cookies in use by a certain browser? Might be a cool feature.
D the OP (heh), I replied here to tell you about one example of an Opt-out cookie that
turns itself back on after a week after you opt out (see below). I found this out by accident months after opting out, so if you are concerned about that Opt-out cookie, check it after a while to see if it stays opted out!
Example: The QuickDrag FF add-on has had undocumented, hidden malware since at least 2013, possibly 2011! See
https://addons.mozilla.org/en-US/fire... for a well researched explanation in the QD reviews.
You can only "opt-out" if you know the Enable Marketing option was quietly added & selected by default, and even if you deselect it it reverts back to selected in one week!!!