Indicator for available DetailRowExpression

I would appreciate a visual marker when a measure has a defined DetailRowExpression. (like a small R in the Measure Icon). Additionally: - better distinction in Expression Editor ( Expression vs. Detail Rows Expression) - visually - to prevent confusion - When Detail Rows Expression is visible for Measure A and I select Measure B - the window sets back to Expression. I would prefer it to stay on the prior selected Detail Rows Expression view.