I’ve seen a product (forget the name) that does the opposite signalling. USB powered RGB light dongle on your desk/cube. Red means “don’t interrupt me unless

I’ve seen a product (forget the name) that does the opposite signalling. USB powered RGB light dongle on your desk/cube. Red means “don’t interrupt me unless the building is on fire”, orange was “don’t interrupt me” , green was “feel free to bug me with that question” I’m sure they could be repurposed the way you suggest. But don’t most people in open spaces use slack or equivalent for that?