GM.JS
Use native JavaScript in GameMaker: Studio!
This HTML5 extensions will allow you to execute native JS from within your game. This will allow your game to become a full blown web app by giving you access to everything that JavaScript can do. GM.JS is especially handy if you are hosting your game yourself.
The four included functions allow you to:
This extension has been tested in all major browser to ensure it works properly. Documentation in the form of a PDF is included, and has clear descriptions and examples of the included functions.
End User Licence Agreement (EULA).