Doesn't work with 67.0.1 (64-bit) version.
While opening "Manage All Cookies" the list of domains is empty.
Answer from the author:
Go to the add-ons page, click on the "Cookie Quick Manager" add-on to get to the details page for the add-on, scroll down to the part that says "Run in Private Windows" and select the "Allow" option.
Until I did this the "All" context would not show anything and some of the other contexts would also be missing cookies. I assume this is because when it tried to enumerate all the cookies, it would hit the "private" cookies and was denied access and instead of just continuing it would halt/crash the add-on.

WHO KNOWS what Mozilla was thinking when they took a step *backwards* in terms of empowering users to manage their own Security & Privacy by removing the ability to View Individual Cookies... but the up-side is that it caused me to discovered THIS add-in, which is *infinitely better* than Firefox's old built-in features.

Ten minutes with this app and I've already learned a bunch of stuff I didn't realize before, in terms of who's tracking me how/where/when, PLUS the ability to modify your cookies so that you're sharing what you want to, when you want to.

Now all I need in an in-depth tutorial about different types of cookies, pros/cons, and so on.

Great job Ysard, thank you.

The best cookie manager I have tested (and I have tested a lot, if not them all!) The pop-up menu shows all the expected options for quick use (find and delete), plus, it also has a convenient option to delete Local Storage, what can be really handy (in a quick glance, it informs if the site is using local memory, giving the option to clear it).

Great extension, very well done. I noticed a recent change: for cookies that are in a Firefox container, the container icon no longer appears. It used to be just to the left of the number of cookies for the site, in the Domains column - ?

it does exactly what I expect

I em surprised< it is an app to have the full control about the cookies. Good job!

Cookie Quick Manager is a very complete cookie manager with an ergonomic user interface. Unlike other addOns, it allows you to edit, backup, restore cookies, search them by domain names and so on. This addOn is perfect for who has a clue of what he/she is doing and is not only looking for a "delete all cookies" button.
The developer is also attentive to his users.
Great work, carry on!

Great add-on, everything works as advertised, developer is ready to help everyone - even those who never read description text. Great work, thanks for sharing.