For Arduino, Circuit Playground Express, ESP-8266, ESP-32, Robohat-MM1, and Raspberry Pi Pico boards, install the server firmware. See the Preparing Your Micro-Controller section of the User's Guide.
Launch the Scratch3 Editor using either the online or offline sites described in the Ready, Set, Go/Launch The Scratch3 Editor section of the User's Guide.
Select your extension and start coding!.
This project was developed with Pycharm