Important! READ FIRST: REMIX THE PROJECT To create your own extension, first remix the project then (inside the 'Use this model!' sprite go into the costumes tab and) fill in the description with what it does, the symbol and the image, then share the project and I will add the extension in the custom blocks tab with it's functionality. Put in the 'collaboration with' part your username, so it is shown as your extension. You an also change the colour of the background.
Look at extensions here ---------------------------> Look at them here! V