After accidentally cracking the micro SD card that my Pi Camcorder boots from, I started using it's built in Pi 4 for OS testing. I started with Ubuntu Server 20.04.1, then screwd up and updated it to a desktop version. That's all fine and dandy, but I want to give Ubuntu Mate 20.10 a try, as it's got a build for the Pi 4 that has GPIO and such set up. I don't want to download it over my phone hotspot, so I'll have to get it later. If that goes well, I could get familiar with it on the camcorder project, then implement a stripped down version for the Cartridge OS. I found in the docs that Ubuntu Mate 20.04 can't be booted from USB on the Pi, but 20.10 can. As much as I want a barebones OS, I don't know enough about Linux to build one, so I'll just start with a nice desktop OS.