Bug 58095 [Preferences] Selecting pref page moved dialog to other screen
When I move the preferences dialog to my secondary screen and change a prefpage, the entire dialog moves back to my primary screen and "hugs" the right border of the main screen.
bundles/org.eclipse.jface/src/org/eclipse/jface/window/Window.java
* adjusted position such that the window is no larger than its monitor,
 * and does not extend beyond the edge of the monitor. This is used for
 * computing the initial window position, and subclasses can use this
 * as a utility method if they want to limit the region in which the
 * window may be moved. 
 * 
 * @param preferredSize the preferred position of the window
 * @return a rectangle as close as possible to preferredSize that does
 * not extend outside the monitor 
 * 
 * @since 3.0
 */
protected Rectangle getConstrainedShellBounds(Rectangle preferredSize) {
	Rectangle result = new Rectangle(preferredSize.x, preferredSize.y, 
			preferredSize.width, preferredSize.height);
	Monitor mon;
	if (parentShell != null) {
		
		
		mon = parentShell.getMonitor();
	} else {
		
		
		mon = shell.getMonitor();
	}
	
	Rectangle bounds = mon.getClientArea();
	
	if (result.height > bounds.height) {
		result.height = bounds.height;