> At the very least, you need to flash a warning up on screen and accept a user acknowledgement, which means you need display drivers, USB, and so on all workin

> At the very least, you need to flash a warning up on screen and accept a user acknowledgement, which means you need display drivers, USB, and so on all working in the boot ROM. Pretty sure Apple has some form of this. On Intel Macs, the boot picker [0] supports displaying text and graphics, accepting keyboard and mouse input, and even connecting to Wi-Fi. There’s also the FileVault password screen, which does not live in the firmware, but it’s a full-screen UEFI app resembling macOS’ login UI. It’s also a thing in the PC world these days. The UEFI setup menu on modern machines is a bitmap-graphics GUI with mouse and keyboard support, for example [1] (a random YouTube video). [0]: https://www.ninjastik.com/support/how-to-choose-a-startup-disk-on-your-mac-to-boot-from-usb/ https://www.ninjastik.com/support/how-to-choose-a-startup-di... [1]: https://www.youtube.com/watch?v=Q1NDjD2RuGM https://www.youtube.com/watch?v=Q1NDjD2RuGM