I call this a bug, would you? If the scaleFactor of stack “myStack” is set to 2, then within(stack “myStack”,the screenMouseLoc) only returns true if the mouse is within the rect of stack “myStack” when it’s scaleFactor is set to 1. Hope I explained that logically. Mac 10.12.2, LC 9.0.0 dp 6. Worked correctly in LC 7. -Dan