I hope the fix is ​​not simply refusing to recognize these boxes, because there may be cases where the top of the box is blocked by a transparent block but you still want the copper golem to classify it.
This seems to be caused by the top of the box being blocked by a transparent block, such as glass or piston. When it is not blocked, there seems to be no recognition problem.
This video demonstrates how boxes covered by transparent blocks seem difficult to target, but this problem does not occur on flat ground.