At the moment, ModernZ implements chapter skip buttons in the center

On mpv's stock osc, it's like this:

Why am I considering this idea:
- It places relative buttons in the focused area, where they're needed
- It reduces footprint of buttons
- It would allow in the future to add a "side" layout, where the controls are shown similar to Youtube, without it being too crowded
So they would be added left of chapter title, with a matching size in:
