Directly from the editor, you can explore the online library of extensions (also called a "package manager" or an "extension store"). Extensions can bring new behaviors for your game objects, or actions, conditions or expressions that are ready to use in events.
Featured extensions are peer reviewed. They are ideal to add new features at a fast pace to your game, making both prototyping of new games a very quick process and allowing larger games to be constructed by assembling extensions.
All extensions can be exported to a file. They can easily be shared and integrated to another project. Better, if you have created a useful extension, you can submit it to be integrated to the library of open-source, community extensions.