[gentoo-user] Gentoo RPi boot to ram or read-only FS?

[Frank Tarczynski]

I'm building a video conference appliance using a Raspberry Pi 4 for my
parents.

I'm using a RPi 4 that boots from a SD card and an USB webcam/microphone.

Gentoo is the only OS I can find that supports the USB webcam in both
Firefox and Chromium with no issues.

Getting my parents to understand that they need to shutdown the RPi before
hitting the power button is a challenge. And I've not been successful at
finding a case for the RPi 4 with a soft power switch and a fan.

Does anyone have pointers for booting Gentoo in to ram? Or a mode with a
read-only FS? Like the overlay mode in Raspbian?

Thanks.
Frank