Changing Object Stacking Order
Each object you create occupies its own position in the Paint operator stack and is represented by a name in the Timeline. As you draw, make selections, or add effects, each new object is added to the active viewport in front of the other objects. In the Timeline, the new objects are above the other object. You can change the stacking order of the objects in your branch at any time. Changing the appearance of the objects and the effects may affect the underlying clip or still image.
For more information, see Stacking Order.