In the revision 11659 was changed behaviour of the "Center Caret On Screen" action (C + e C + n): "- Center Caret On Screen now scrolls your document so your caret doesn't change. [ 1883809 - ezust ]" But for that purpose we have the "Scroll to Current Line" (C + e C + j) action. The "Center Caret On Screen" action is supposed to change the caret position.