My video movies on my windows 11 pc have been either downloaded or copied from DVD’s. I view them on my Samsung smart TV using Amazon Firestick with Plex app. It seems that the picture is over scanned because some text on the edges of the picture is cut off. And there are no top and bottom black borders on a 16:9 image. The picture fills the tv screen completely which I assume is an overscan issue. I’m not sure if the issue is with Firestick or Samsung tv or Plex. Regardless, I switched to viewing my movies using FireTV with the Jellyfin or VLC apps and the movies play back perfectly with well synced subtitles and no text cut off at the lateral edges of the video. And the 16:9 ratio is maintained. Go figure??
If the setting still exists (I’ve not looked in awhile), make sure Display Mode = Letterbox.