When dragging frames around, you'll see bright lines appear.
These lines are allignment guides, that align with other objects and reference points on the canvas.
The object you drag has several referenes to align to
- Frame borders
- Frame center
Guides appear when allignment to these references is close to
- Layout borders (top, bottom, left, right)
- Other frame references (top, bottom, left, right, center)
Have you found the easter egg in the GraFx Publisher snapping settings?