Hi Tom,
> FWIW, I tried to replicate this locally on my own RPi3B+, using
> current Ubuntu 20.04.4 LTS (GNU/Linux 5.4.0-1066-raspi aarch64).
> No luck: it all works fine for me. We have at least one Raspbian
> buildfarm animal too, and it's not been unhappy either. I suspect
> there is something odd about your environment settings.
Thanks for sharing this.
I repeated the experiment in a clean environment (Raspbian installed
from scratch on a brand new SD-card) and can confirm that the problem
is gone.
Sorry for the disturbance.
--
Best regards,
Aleksander Alekseev