It seems that the whole preceding thread is focused on the wrong point.
The initial writers want a "non-tool" because they want to click on the
image window without doing anything. But why do they want to click it?
Certainly only for giving it the focus.
That means that they are doing it the wrong way, even if they are doing
this all the time. With a decent window manager, you have the option to
give the focus to a window as soon as the mouse pointer is above it.
With any window manager, you can focus on a given window by clicking on
its title bar, or by using some key combination like Alt-TAB.
Use one of these possibilities, make it an automatic action, and you
will never again need to click anywhere on a window without wanting to
do something there.
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