It would be very convenient if clicking an already opened application in the Dock switched to the space that application window is located on. For example: I have Mail assigned to Desktop 2. I’m on desktop 4 surfing safari. I click on the Mail Icon on my dock and it activates the Mail App but doesn’t switch to the desktop the Mail Application is located on: Desktop 2.
Ok, so I figured it out. I had previously disabled spaces and mission control via defaults. I had to undue that then the switching came back. Details on how to do that here: