Why Can't Object Desktop Display Different Instances of Edge as Separate Dock Icons: AltTabby Can!
Object Dock used to be able to display separate dock icons for different running instances of an app. The settings are still present in Object Dock but are unmodifiable. The official answer is that in current versions of Win10/11, it's no longer possible to display icons for separate running app instances. In the image below, the circled setting cannot be unchecked in the current release of Object Dock 3 (why show it if it doesn't work and just confuses users?!).
However, in AltTabby, the app is smart enough to enumerate separate Edge instances and even assign them the proper icons (which were assigned to the Object Dock shortcuts that launched both Edge proper and Toodledo as an Edge PWA). In Object Dock, if you assign the PWA the Toodledo icon, the Edge app running on its own will also display the Toodledo icon. What a mess!

Great that I need to run another Stardock application (AltTabby) to make up for the shortcomings of the latest, greatest version of Object Dock 3.