EDIT : Thank you to
🌟 Firefox user 14923258 🌟 who posted
on May 05 at approx 17:50 EST :
[ [ I myself have not done the following. Luckily having updated to FF 66.0.4 at approx 19:00 today, May 5 th, has returned μBlock Origin from a 0 functional extension to a Mega, as in M symbol + Hero :grin: , extension again. ] ]

For those who are having issues as of recent
try to go to about:config in the url bar
xpinstall.signatures.required
set to false
its a temp work around..until developer fixes
tutorial in link
https://www.ghacks.net/2015/06/19/how-to-disable-the-firefox-40-add-on-signing-requirement/
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Hi all...
Oops, I forgot the 1st reason for my post:
Regarding shared thoughts by "BHJ" on March 28, 2019 :

Works quite good and have done so for a long @ss time now :) But whats up with the "Store unlimited amount of client-side data" ? I am not to sure about that. :S

* Oby * — : ⬆️ Ditto … Please help anyone who can constructively enlighten us.

I don't have a constructive criticism about μBlock Origin ( btw : μ= micro / "a millionth of", & M= "a million of" / mega. Among the spoken or written Latin / Greek / English etc world, it began to be globally adopted in 1873. μ / micro is from the Greek μικρός ( mikrós ), meaning "small". Sorry, I geeked🤓out. ( Thanx WikipediA ).
So, for other fans who enjoy "micro B O" ( hey, way better than having "Mega B O" 😸 ) by Raymond Hill, since I guess there are branches of the source(s) of "μBlock" / "μBlock Origin" out there, I have a suggestion to reviewers who's comments are along the lines of :
It's very good, but it has "things" regarding "parts" of the user interface that need to be more "easy to use" ...
Please, give this a chance :
Take a few minutes now-&-then to jot down between 1 & 3 things U want ( There is no "U" in "important", but
to me You ✨ like a Mega-🌟 ! … well unless U spell it "empourtent" 😏 ) to see changed sooner instead of way later. And, for one of those, describe it very well, or include a link to one or two images you can create following this :
( 1 ) ➡️ Once your μBlock Origin screen has what you'll want to paint your ideas onto an image copy, press your [ PRINT SCRN ] button.
( 2 ) ➡️ Open a paint program
( 3 ) ➡️ Once you're past any pop-ups etc, & it's window is active, type [ CTRL + V ] to paste the screen-grab placed into the paint program screen ( copied into your clipboard in step ( 1 ).
( 4 ) ➡️ Take a moment "4" *saving* your sanity = Save this now "As it is". Then, keep saving new images with slightly diff names ( ending " - 00.png", "- 01.pg", etc, or what-not ) as you blacked out all parts of the screenshot that you don't want others to read. I, btw, save my diff files with endings of " - 2019 04 04 at 23;22" … ( but your date & time, :grin: ).
( 5 ) ➡️ Doodle ( or, be snazzy ) an arrow / arrows(s) to show where to move a GUI element / combine elements. Also, use the paint program's "entering typed text into image, with ability to move the text around before clicking paste" ( remember, making multiple saves, saving with edited ending of the current date / time on each one, is super smart. )
So, show-off your "More Gratifying Graphical User Interface" idea(s).
Who knows, you may see :
* Thanks to "Your Name Here" for the idea * - in a future version log.

Please Note : I've got no connection to this extension or it's creator(s). I'm just a middle-aged computer techie 🤓
 ( with varied know-how in ~ 20 home computers etc, e.g. , https://en.wikipedia.org/wiki/List_of_home_computers#Manufacturers_and_models , and a humankind luvin' schmoe, providing some hopefully useful advice that will accelerate the growth in quality of "ease of use of things" while keeping and widening the feature-richness of μBlock Origin, if just 10% percent of reviewers give it a go.

This is an excellent adblocker, probably the best you can find for Firefox and other browsers; it does a great job blocking all ads, and it is also open source, a near guarantee of security and privacy.

The interface is very outdated, though--the buttons and layout are not at all intuitive to less robust computer users (thankfully I'm not one of them) and the settings menu can be confusing to the extreme. Though these problems don't apply to me, they do to many, and I think they should be fixed.

Aside from the UI, uBlock Origin is the best adblocker available for Firefox.

Your picker tool for selecting element to block is not accurate. I tried it to block related videos in YouTube site and it failed to select it successfully.