Several minor changes were made to The Firefox Privacy Guide For Dummies! article. If you've slugged your way through the guide before, there's probably no reason to re-read it, but i will mention a few reminders...
Remember to run the 'ghacks' updater script occasionally (twice a month or so) to check for a new version of their user.js preferences file (make sure you exit Firefox prior).
Every time you run the updater script and it downloads a new version of the user.js, be sure to follow it up by running the prefsCleaner script. This is probably more important than you think.
I highly recommend NOT using any other flavor of Firefox other than the official release by Mozilla; no Waterfox, no Pale Moon, no whatever. These non-official builds often run (well) behind the Mozilla release cycle and therefore behind in security patches as well. Your web browser is your gateway to the Wild World Web and is therefore a most appealing target for malicious hackers which are lightening fast in exploiting security holes.
The privacy and security risks associated with 3rd party builds isn't worth the risk in the opinion of some very knowledgeable people. I mention this because i still see here in comments and emails where some people are running 3rd party builds. I fully understand the attraction to developers offering privacy hardened builds of Firefox, but understand that there is little, if anything, that they offer which cannot be accomplished with the official Mozilla version.
Among all of the capable web browsers out there, including Chromium, Chrome, Edge, Brave, Waterfox, etc., it is my opinion that Firefox is the only web browser available at this time which is best suited for the privacy conscious user. I am not a Firefox fanboy and so it is not with enthusiasm that i make such a statement, but i believe it to be factual at this time. Hopefully this will change in the not so distant future because i really dislike the direction Mozilla has taken with Firefox, their constant dumbing-down of their browser, and some of the utterly asinine decisions they've made, but for now it is what it is.
Lastly, don't apply either of my Firefox config guides to the Tor browser, else DOOM!