Add a setting in each video track to determine the number of video thumbnails showing up in each clip.
- first (first frame of the clip on the beginning of each clip)
- show first and last (first and last frame of the clip on the beginning and the end of each clip)
- show frames (continuous video thumbnails)
- show name only
The number of frames displayed should be depending on the selected height of the video track and the zoom of the timeline.
- The height of the video track determines the number of the thumbnails displayed: the height of the video track is the height of the video thumbnail.
- Smallest video track (min. height of the video track) showing most frames
- Highest video track (max. height of the video track) showing fewest frames.
see more info here: https://forum.kde.org/viewtopic.php?f=265&t=153233#p401721