I think this is a combination of two principles: left click to focus, plus one action per click. So left-click on an unfocussed window raises it instead of performing the usual actions. Other buttons don't cause windows to be raised so their usual actions are not suppressed in unfocussed windows.
I guess it's possible for apps to break this logic and cause inconsistent behaviour.
no subject
I guess it's possible for apps to break this logic and cause inconsistent behaviour.