I don鈥檛 know what category this would be under but, I think it鈥檚 definitely worth adding.
Lightbeam basically displays all first and third party domains you consciously or unconsciously connect to and how they connect to each other, when you are browsing the web.

https://addons.mozilla.org/en-US/firefox/addon/lightbeam
https://github.com/mozilla/lightbeam-we
P.S.
Lightbeam is not designed as a tracker or ad blocker, instead it is designed to show users who actually is tracking them, so they can take appropriate action If desired.
Useless addon. It doesnt block anything and all Blocktools show which and how many are blocked
@beerisgood
I could be mistaken but I don鈥檛 think that is really the point of Lightbeam.
I think Its more designed to show sites that are tracking you and some of what they can see, like what domains you have visited but in a graphical lay out.
Not a privacy addon per se, but might be useful to show the user the measure of online tracking.
Once you are aware who鈥檚 tracking you, It can be used to manually block domains to limit tracking.
Although, this currently isn鈥檛 built in and is lightly more for advanced users but, it鈥檚 still useful to see what鈥檚 going on.
Once you are aware who鈥檚 tracking you, It can be used to manually block domains to limit tracking.
Use PrivacyBadger.
Informational extension that does nothing for user's privacy per-se.
Just be aware that when Firefox Multi-Account Containers is installed, Lightbeam only shows data for "No container" tabs.
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Just be aware that when Firefox Multi-Account Containers is installed, Lightbeam only shows data for "No container" tabs.