I want to be able to create additional instances of the property window that watch a specific object.
Often, especially when debugging, you’ll want to watch and iterate on more than one object at a time. Consider some physics assembly that involves two cylindrical constraints and a hinge. You can’t just select everything because you’ll be editing and viewing both cylinders at once. You have to select each object separately every time you want to tweak the assembly.
This makes iteration slow and annoying, especially for objects that are iterated on during runtime using the properties window.
I want to be able to right-click an object in the explorer to open up a properties window that focuses on that object and doesn’t change with my selection.
Edit: Another good example is any structure of same-type objects that play different roles. Such as a particle emitter system or a UI object structure.