The problem is that when a user launches Outlook Edge also launches a blank white screen that fills the screen.
In essence the solution is to sign out of Edge profile and then launch / close Edge
To sign out of Edge click on user symbol on top right side of Edge (it’s left of the three dots)
Click on “Manage profile settings”
Under “Your profile” click on “Sign out”
Click “Sign out” on the next pop up.
Then close Edge, launch Edge again, close Edge
Outlook should now launch without the Edge white screen appearing