Don't confuse "window rules" with "application rules". When configuring rules, you normally want the latter unless you know you want the former.

Also don't forget that rules can interact with other rules. For example, window size interacts with all of: "fullscreen", "maximized", and the "geometry" options (commonly set to more than 1 pixel for terminals).

That said, I am really not a fan of the recent UI-pessimization of the settings screen to require you to type out the setting you want rather than have tabs listing all the various options in a discoverable manner.