Bug 319173 [UI] Resizing feedback stops working
While we have seen this on other platforms we have a repeatable test case for the Mac (bogdan, please check if this is the exact scenarion, I'm entering it from memory): Fresh WS, open two other perspectives hit Ctrl-F8 (select perspective) Resize the main window the feedback for the resize doesn't occur until after the mouse button is released.
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/ui/workbench/renderers/swt/TrimBarRenderer.java
* 
	 * @see
	 * org.eclipse.e4.ui.workbench.renderers.swt.SWTPartRenderer#childRendered
	 * (org.eclipse.e4.ui.model.application.MElementContainer,
	 * org.eclipse.e4.ui.model.application.MUIElement)
	 */
	@Override
	public void childRendered(MElementContainer<MUIElement> parentElement,
			MUIElement element) {
		super.childRendered(parentElement, element);
		
		if (element.getWidget() instanceof Control) {
			final Control ctrl = (Control) element.getWidget();
			ctrl.addControlListener(childResizeListener);
		}
	}
	protected void cleanUp(MTrimBar element) {
		ArrayList<ArrayList<MTrimElement>> lists = pendingCleanup
				.remove(element);
		if (lists == null) {
			return;
		}
		for (ArrayList<MTrimElement> list : lists) {
			for (MTrimElement child : list) {
				element.getChildren().remove(child);
			}
		}
	}
}