I want to display two 3d view windows at once. But I want one to be in Edit Mode, and the other in Object mode. However, when I change the mode of one window the other 3d view window automatically changes. How can I make it so changing the mode in one window does not affect the other window?
I will assume you want to have one area in object mode for a clean and overlay free preview, while still being able to edit your mesh as usual.
This can be achieved by disabling the overlays and gizmos in the top right of the 3d viewport.
This way edit mode is not disabled, but you don't have any wireframes or selection highlights. This should work for any other mode as well.
If you need the other area to be in object mode I'm afraid that is not possible as far as I know.