post_upgrade() {
  local new_pkgver="$1" old_pkgver="$2"
  if [ "$(vercmp "$old_pkgver" 1.0)" -lt 0 ] && [ "$(vercmp "$new_pkgver" 1.0)" -ge 0 ]; then
    cat <<EOF
You may get the following error when trying to run mirage after upgrading from ${old_pkgver} to ${new_pkgver}:

Traceback (most recent call last):
  File "/usr/bin/mirage", line 30, in <module>
    app = mirage.Base()
  File "/usr/lib/python2.7/site-packages/mirage.py", line 227, in __init__
    self.read_config_and_set_settings()
  File "/usr/lib/python2.7/site-packages/mirage.py", line 714, in read_config_and_set_settings
    self.bgcolor = gtk.gdk.Color(red=bg['r'], green=bg['g'], blue=bg['b'])
TypeError: list indices must be integers, not str

This happens because the config format was changed in 1.0_pre1. To fix this
issue you can try deleting ~/.config/mirage directory, although you may want to
copy contents of ~/.config/mirage/miragerc if you made any changes to it. The
new config is located at ~/.config/mirage/mirage1.conf
EOF
  fi
}