title: JavaScript: Check if mouse button down?
body: <p>Is there a way to detect if a mouse button is currently down in JavaScript?</p>
  
  <p>I know about the "mousedown" event, but that's not what I need.  Some time AFTER the mouse button is pressed, I want to be able to detect if it is still pressed down.</p>
  
  <p>Is this possible?</p>