This is a browser extension for the game Die2Nite. It is compatible with the English, French, Spanish, and German versions of the game.
The extension was adding a bunch of features to make the gameplay more enjoyable. Most of the modifications were happening at the UI level, but it also provided integrations with third-party services. It was one of the most popular extensions for the game at the time, and was regularly recommended.
It was published on the Chrome, Firefox, Opera, and Safari stores. Furthermore, it was also available as a GreaseMonkey script.
The extension was developed with Vanilla JS, with a handmade layer of code to allow cross-browser compatibility.
I stopped working on the script when I stopped playing back in 2014. But the project was forked and is still actively maintained.