Javascript Runner is a free Chrome extension developed by namata that allows users to execute Javascript code on site pages after they have been fully loaded. With this extension, users can easily run custom Javascript code on any website they visit.

The extension is simple to use. Once installed, users can simply click on the extension icon to open the Javascript Runner interface. From there, they can write their Javascript code and press "Set" to save it. The code will then be executed each time the page on the site is fully loaded.

This extension is particularly useful for developers and users who want to customize their browsing experience. It allows them to add functionality and make changes to websites by running their own Javascript code.

Overall, Javascript Runner is a handy Chrome extension that provides users with the ability to run custom Javascript code on site pages. It is easy to use and can enhance the browsing experience for those who want to customize their online interactions.