A great discovery today: fwupd capsule updates using coreboot!
https://novacustom.com/introduction-of-fwupd-support-capsule-updates/

Introduction of fwupd support + Capsule Updates - NovaCustom
For easy installation of firmware updates. Firmware updates were unnecessarily complex for a long time. They required manual command line steps, were error-prone, and carried a real risk of “bricking.” In addition, updates often depended on specific BIOS settings. If something was wrong, an update could fail. This not only caused frustration for users, but ... Read more