How to chain u-boot with something that I don't understand.

[Ralf Mardorf]

On Sat, 2023-07-01 at 19:27 +0200, Ralf Mardorf wrote:
> extlinux mailing list
  ^^^^^^^^ this should read "syslinux"

FWIW https://tracker.debian.org/pkg/syslinux so you can see that
extlinux is a part of syslinux.