"fatal: error opening or reading config file ' /etc/xdg/weston/weston.ini.default'" when trying to start Weston

(at least) on Sony Ericsson Xperia mini Weston is unable to launch due to it not being able to read it's configuration file, which is supplied through the WESTON_OPTS environment variable, which is set in start_weston.sh script, which is being launched by LightDM on boot. If I set the WESTON_OPTS variable to --config=$cfg, as opposed to -c $cfg, in the start_weston.sh script, then Weston is able to launch.

logread from Xperia mini: https://gitlab.com/snippets/1916506