While playing a video, laptop screen gets locked and even it gets suspended. there is no way to configure the player to prevent this event. also this version I'm using doesn't provide that much of configuration options but just a few ones: open, stop, mute, subtitles, audio track, video track, about. and that's it. these few options also are just available via clicking a small button on a hover-able bar which gets faded soon.
A possibly relevant merge request was started @ https://invent.kde.org/multimedia/dragon/-/merge_requests/70