+@vindex x-mouse-click-focus-ignore-position
+Normally, Emacs does not distinguish between ordinary mouse clicks and
+clicks that select a frame. When you click on a frame to select it,
+that also changes the selected window and cursor position according to
+the mouse click position. On the X window system, you can change this
+behavior by setting the variable
+@code{x-mouse-click-focus-ignore-position} to @code{t}. Then the
+first click selects the frame, but does not affect the selected window
+or cursor position. If you click again in the same place, since that
+click will be in the selected frame, it will change the window or
+cursor position.
+