ghost
commented
1 year ago this can happen if there are chapters or some kind of length metadata that wasn't modified from the original file. for instance, if the chapters go up to 5 minutes, then your operating system and video player will think the video has 5 minutes, even though the video stream only has 1 minute. try loading it to mkvtoolnix, then removing all elements besides video and audio, and then multiplexing it to a new .mkv file.
After cutting the length of the video remain the same. For example, video was 5 min length. After selecting, cutting and saving 1 minute clip the size of the file reduced. But in video-player shows that the length of the new file is 5 min. If play, then after 1 min it stops... Ubuntu 20. Installation via flatpak.