Sb3.zip Site

Once compiled, the extension's data will be stored within the project.json whenever the user saves their project as an .sb3 .

If your goal is to add a new functional block inside Scratch itself: You must develop a Scratch Extension using the Scratch VM. sb3.zip

: You can use standard ZIP libraries to extract the project.json , modify the blocks or variables within the JSON, and then re-zip the contents back into a .sb3 format. 2. Version Control Features Once compiled, the extension's data will be stored