Timeline autoscroll does not work with lower zoom levels

Steps to reproduce:

1. Create a timeline
2. Add rectangle item to form editor
3. Animate e.g the position of the rectangle, adding keyframes to timeline start frame and end frame
4. Click "Zoom in" button a couple of time in the timeline
5. Try moving playhead to end frame  -> won't autoscroll
6. Click "Zoom in" button two times more
7. -> Autoscroll works now