Thanks! That's for incoming calls and I have that option checked already. What I meant was a little green window (or simply a bar) floating on the screen when you're on a call and the dial window is in the background (you're doing something else). It allows you to tap on that window to get back to the dial window. Not sure if I explain it correctly.
Originally Posted by mjones73
Is this this option?
Open the dialer, settings, Incoming voice call pop-up.