The linux-firmware package created from build-linux-firmware.sh in the vyos-build repository does not consult the WHENCE file for additional symbolic links that need to be created, resulting in many missing firmware files.
A concrete example of where this matters occurs with the Intel E810-series NICs utilizing the ice kernel mod and requiring a symlink at intel/ice/ddp/ice.pkg or else the NICs enter a failsafe mode incapable of performing much beyond basic forwarding.
The missing symlinks should be added into the vyos-linux-firmware package along with the link targets in order to prevent missing firmware files from causing incorrect/sub-optimal behaviour.
Relevant PRs:
https://github.com/vyos/vyos-build/pull/262
https://github.com/vyos/vyos-build/pull/263
Tested on Equuleus 1.3.1 bare-metal using an Intel E810-XXVDA4 network adapter.