I would like to enable click-through on all windows. Is this possible on Lion?
To be more specific, "click-through" as defined by Apple in the Mac OS X Human Interface Guidelines means "that the user can activate the item when the containing window is inactive."
An item that provides click-through is one that a user can activate with one click, even though the item is in an inactive window. (To activate an item that does not support click-through, the user must first make the containing window active and then click the item.) Although click-through can make some user tasks easier, it can also confuse users if they click items unintentionally.