Just by installing the extension and setting a specific blacklist rule in a new browser window, I could block a stupid-ass scammer website that denied me all access to my browser, without needing to close all tabs in my first browser window. Very nice!

Facil de usar y ofectiva

Doesn't do shit! I mean, it really is not working for even the simplest cases. What is this?

It has a very serious bug for the whitelist setting. It only works on the first window. It doesn't block ANYTHING when a new window is opened. That being said, everything work perfectly on the first window. Fix that bug then we can use it for our school computers. I need to only allow access to the URL(s) for our tests.

I would love it to be able to sync the blocklist.

It takes 1 full second after the site will be blocked. Its useless when sites redirect you.

easy, simple and doesn't eat my memory.
'Nuff said!

It used to allow wildcards.

lets me block exactly what I want and nothing else.

Much worse than previous releases. It does a very poor job blocking sites. I am looking for another blocker. It used to work but now very ineffective. Letting a lot of sites I thought I had blocked through. Wildcards are no longer allowed so all the offending site has to do is make a small change and it gets through.

BLOCKS ALMOST NOTHING!!!

Blocking in the new version for FF 57 does not work in many cases. E.g. I have this file blocked and yet it is loaded. Before all worked as expected.
apps.[removed].sk/[removed]/js/jquery-1.11.1.min.js

Old version was very useful, the new one is useless.

Good

If you open up a second firefox window then on this window the sites are not blocked anymore

It does the thing that I installed it to do: block sites. User interface is plain and simple, which I like.

basic and beautiful interface

The URLs in my Block-List always are destroyed by themselves. At least: It seems so to me. But - may be its the final proof of extraterrestrial life.
If the Blocklist is activatet the URLs come up inspite of it. Withput my activity. So I think by myself - is it a stupid joke - made by the MOZILLA-staff ?
The Blocklist-addon seems to me absolutely useless.
But - may be Im only a 60 years old idiot.......................................
Warm regards
Thomas