| 12345678910111213141516171819202122232425262728293031 | FROM debian:stretch# Setup demo environment variablesENV HOME=/root \    DEBIAN_FRONTEND=noninteractive \    LANG=en_US.UTF-8 \    LANGUAGE=en_US.UTF-8 \    LC_ALL=C.UTF-8 \    DISPLAY=:0.0 \    DISPLAY_WIDTH=1024 \    DISPLAY_HEIGHT=768# Install git, supervisor, VNC, & X11 packagesRUN set -ex; \    apt-get update; \    apt-get install -y \      bash \      fluxbox \      git \      net-tools \      novnc \      socat \      supervisor \      x11vnc \      xterm \      xvfbCOPY . /appCMD ["/usr/bin/supervisord", "-c", "/app/supervisord.conf"]EXPOSE 8080
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