This is very odd. I found a typo in my apt-cacher configuration, fixed it. Rerun my apt-cacher auto-creation script and get it working. But just once! I redo the librewolf qube creation and it failed again with the same (old) error message.
May I ask you to briefly run these 6 code lines (Qubes OS 4.2, apt-cacher installed and configured):
src="debian-12-minimal"; tpl="deb-12-m-librewolf-extrepo"
get the Debian 12 minimal template
qvm-template install ${src}
make the apt-cacher modifications
qvm-run --pass-io --user root ${src} 'sed -i s^https://^http://HTTPS///^g /etc/apt/sources.list'
qvm-run --pass-io --user root ${src} 'sed -i s^https://^http://HTTPS///^g /etc/apt/sources.list.d/*'
qvm-clone ${src} ${tpl}
qvm-run --pass-io --user root ${tpl} "apt install qubes-core-agent-passwordless-root qubes-core-agent-networking"
qvm-run --pass-io --user root ${tpl} "apt update"
qvm-run --pass-io --user root ${tpl} "apt install extrepo --yes"
qvm-run --pass-io --user root ${tpl} "http_proxy=http://127.0.0.1:8082 https_proxy=http://127.0.0.1:8082 extrepo enable librewolf"
I end up with this error message (in dom0):
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
LANGUAGE = (unset),
LC_ALL = (unset),
LANG = "en_US.UTF-8"
are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
Could not download index YAML file:
500 establishing SSL tunnel failed: 403 CONNECT denied (ask the admin to allow HTTPS tunnels) at /usr/share/perl5/Debian/ExtRepo/Data.pm line 27.