seekbar cursor doesn't map correctly to actual playhead position
Steps to reproduce.
- Open any video (local file)
- Pause it.
- Click on the cursor on the seek bar and hold the mouse button pressed (i.e. drag it) 4- drag the cursor slowly only FORWARD
Expected: as you move the cursor forward, the video should only skip forward (or not skip at all when you don't move the cursor enough)
Observed: the video randomly jumps a few frames forward, then a few frames backward, and so on.
That the mapping from cursor position to actual playhead position is not 100% accurate may be expected (though it is completely possible to have it 100% accurate) but it must at the very least be monotone.