maxDepth

how deeply a surface may nest before drawing stops. The default is derived from two measurements: the official example corpus needs 7 levels at most (median 5), and the point where composition breaks moves with how many frames a widget nests per level -- 216 for a plain container, about 36 for a widget stacking six. 24 is 3.4x what real content needs and two thirds of the break for a heavy widget. Both sides have room because the break is neither catchable nor recoverable.