If a window does not have focus, clicking on it should raise it to the foreground and focus it, but it should not pass the click to the window.
There is an app "Klicko" (https://brockerhoff.net/klicko/index.html) that does this, but it has last been updated in 2008 and no longer works on my Big Sur Intel machine.
As you can see, my question is the opposite of Enable click-through, preferrably for all applications
