Toolkit for YouTube. Settings panels for customization. Features include: tab view, playback speed control, set video quality, set transcript language, export transcripts, prevent autoplay, hide shorts, hide ad slots, disable play on hover, square design, auto theater mode, number of videos per row, display remaining time—adjusted for playback speed and SponsorBlock segments, persistent progress bar with chapter markers and SponsorBlock support, modify or hide various UI elements, and much more.
I'm gonna look into it. In the meantime, you can edit the script settings in Violentmonkey under "Custom metadata" and change the "@run-at" setting from "(Default)" to "document-end." This ensures both the head and body are available, allowing the script to load correctly.
Is it possible to make this compatible with Violentmonkey? It's currently the best open source userscript addon for firefox.