sam:haesbaert: rc-service -vU syncthing start
 * Executing: /usr/libexec/rc/sh/openrc-run.sh /etc/user/init.d/syncthing start
 * Starting syncthing ...
 * start-stop-daemon: --stdout-logger and --stderr-logger are only relevant with --background
 * Failed to start syncthing                                                                                                                 [ !! ]
 * ERROR: syncthing failed to start

^ I think it's missing the background function in the init file?