Prerequisite Make sure your problem is not listed in the common build problems. Make sure no duplicated issue has already been reported in the pyenv issues. You should look for closed issues, too. Make sure you are not asking us to help ...
Unable to locate package libva-drm2 I "fixed" this by adding RUN echo "deb [arch=amd64] http://ftp.de.debian.org/debian sid main" | tee /etc/apt/sources.list.d/jellyfin.list before the apt-get stuff. It builds at least but when starting up the container I get the following error...