content: FROM continuumio/miniconda3
  
  RUN \
    echo "debconf debconf/frontend select Noninteractive" | \
      debconf-set-selections
  
  RUN \
    apt update && \
    apt install -y \
      shared-mime-info \
      xvfb
  
  COPY environment.yml /
  RUN \
    conda env create && \
    echo "conda activate ruby-gnome" >> ~/.bashrc
  
  # "gem install", "gem list" and so on don't recognize gems installed
  # by "gem install --user-install"...
  ENV RUBY_GNOME_INSTALL_USER_INSTALL=no
  
  # Adwaita: It's not available.
  # * adwaita
  #
  # Clutter: It's not available.
  # * clutter
  # * clutter-gdk
  # * clutter-gtk
  # * clutter-gstreamer
  #
  # GEGL: It's not available.
  # * gegl
  #
  # GOffice: It's not available.
  # * gnumeric
  # * goffice
  #
  # GtkSourceView: It's not available.
  # * gtksourceview3
  # * gtksourceview4
  # * gtksourceview5
  #
  # libhandy: It's not available.
  # * libhandy
  #
  # libwnck: It's not available.
  # * wnck3
  #
  # VLC: It's not available.
  # * gvlc
  #
  # VTE: It's not available.
  # * vte3
  # * vte4
  #
  # WebKit: It's not available.
  # * webkit-gtk
  # * webkit2-gtk
  ENV \
    RUBY_GNOME_ADWAITA_ENABLE=no \
    RUBY_GNOME_CLUTTER_ENABLE=no \
    RUBY_GNOME_CLUTTER_GDK_ENABLE=no \
    RUBY_GNOME_CLUTTER_GSTREAMER_ENABLE=no \
    RUBY_GNOME_CLUTTER_GTK_ENABLE=no \
    RUBY_GNOME_GEGL_ENABLE=no \
    RUBY_GNOME_GNUMERIC_ENABLE=no \
    RUBY_GNOME_GOFFICE_ENABLE=no \
    RUBY_GNOME_GTKSOURCEVIEW3_ENABLE=no \
    RUBY_GNOME_GTKSOURCEVIEW4_ENABLE=no \
    RUBY_GNOME_GTKSOURCEVIEW5_ENABLE=no \
    RUBY_GNOME_GVLC_ENABLE=no \
    RUBY_GNOME_LIBHANDY_ENABLE=no \
    RUBY_GNOME_VTE3_ENABLE=no \
    RUBY_GNOME_VTE4_ENABLE=no \
    RUBY_GNOME_WEBKIT2_GTK_ENABLE=no \
    RUBY_GNOME_WEBKIT_GTK_ENABLE=no \
    RUBY_GNOME_WNCK3_ENABLE=no
  