Do not install, it will not install and stay away from this extension

Perfect!
I found myself often scrolling through social media and news pages while I was supposed to get work done. They call it procrastinating. This simple yet effective add-on blocks chosen URLs after my set time limit and remind me to focus on my work. Of course there are some workarounds for the block, but this is a solid treshold for work avoiding behaviour.

Its really workin! Thank u!
Guys, use this way for writin sites 4ex - *://*.vk.com/*

Does exactly what it says. Straightforward configuration (from the Add-ons Manager in the menu)

I always liked this extension before the Quantum update and some of the functionality has changed. Is there a way to remove the push notifications that pop up, telling me time is expiring? Thank you.

The add-ons does the job of blocking websites that will steal time through procrastination. However, it could be a little easier to use as websites have to be entered with specific coding e.g. *://*.facebook.com/* but a fairly easy work around is by adding a new line, pasting the above example and replacing the website address inside the special characters. Once the website has timed out, there isn't a prompt saying that your time has expired, it will just reload an empty new tab (unlike leachblock which will display a message), so it's easy for a novice to mistake this for an error. Other than that, can't complain.