Scrubbing previews

Small pictures above the progress bar while you drag through a video. Reelhost turns them on for the libraries you choose; Jellyfin makes them in its scheduled task "Generate Trickplay Images" (every night by default), not all at once, and they appear as each video is done.

With Video speed on, the graphics card does the work. Without it the processor does, so a big library takes many nights and the computer is busy meanwhile: turn on Video speed first if you can.