Custom Stylesheet & Script is a free Chrome add-on developed by Rufflewind. This simple extension allows users to insert custom JavaScript and CSS code into every web page, giving them the ability to modify the behavior and appearance of websites.

By default, the extension does nothing and users are required to provide their own script and stylesheet. An example can be found on the developer's GitHub page. To edit the script and stylesheet, users can navigate to chrome://extensions and click on "Options" under "Custom Stylesheet & Script".

One notable feature of this extension is that the text areas in the "Options" tab automatically save as users edit. However, existing pages are not affected until they are refreshed.

Please note that as of version 2.0.0, jQuery is no longer included with the extension. Users experiencing any issues can report bugs on the developer's GitHub page, and the changelog can also be found there.