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.