Mac Show All Windows for an app in dock Sierra When I had El Capitan, I was able to (or assigned a shortcut to) : when I hovered over a dock icon and scrolled up (with mouse or trackpad), it would show all windows of the dock application i hovered over.  i can't remember now that i have sierra how i did this ; any ideas?
Go with the the mouse pointer to the dock icon in question, then with three fingers go up, this will reveal all open windows of this application.