Very productive. My only quibble would be that it should maintain the URL browsed to in the address bar or on the block page. I often open tabs of blocked sites for later reading only to see the impulse blocker page later on. Clicking on the Add-on button to toggle it on or off would be more convenient.
Anyhow, thanks for the great Add-on.

For unknown reason it blocks ALL sites, so I have to turn it off to just use my browser

So simple. Just glorious.

Sencilla y util

I don't want to block ads, just individual websites. This works perfectly for both my phone and tablet.

It does it's job well but the fact that it's enabled every time I open my browser gets a bit annoying when I'm just trying to relax. There should be a default option for when you open Firefox

Simple and does its work. Nice addition would be option to manually add site. It would be even nicer, if there was possibility to add sites using regular expression to for example block only maps.google.com instead of google.com

So simple but so efficient

Small easy to understand source code, does what it advertises without tracking or making external web requests