"Set the region to the text that the mouse is dragged over.
Highlight the drag area as you move the mouse.
This must be bound to a button-down mouse event.
-In Transient Mark mode, the highlighting remains once you
-release the mouse button. Otherwise, it does not."
+In Transient Mark mode, the highlighting remains as long as the mark
+remains active. Otherwise, it remains until the next input event."
(interactive "e")
(mouse-minibuffer-check start-event)
(let* ((echo-keystrokes 0)