Version 1.7.1 of the
rpi-imager (the latest at the time of writing, and also the current version in the stable channel of the snap) includes the ability to customize the cloud-init (or other “first-run” configuration). Unfortunately this does not currently work in the snap because it lacks the
removable-media connections by default (required to mount the boot partition on freshly flashed images in order to write the customized cloud-init / first-run config).
Would it be possible to add these two interfaces to the auto-connection list for this snap?