Bug 304211 StackRenderer does not set eagerly created controls to the item
Right-clicking on a Java element and then using 'Open Declaration' opens an editor on the specified file but its content is not shown. Switching tabs or selecting items in the 'Outline' view does _not_ help. Seems to be calling IWorkbenchPage's APIs properly. No idea yet as to what's going on over here.
bundles/org.eclipse.e4.ui.workbench.renderers.swt/src/org/eclipse/e4/workbench/ui/renderers/swt/StackRenderer.java
MElementContainer<MUIElement> parent = uiElement.getParent();
				if (!(parent.getRenderer() == StackRenderer.this)) {
					return;
				}
				
				CTabItem item = findItemForPart(uiElement);
				if (item == null) {
					return;
				}
				Boolean dirtyState = (Boolean) event
						.getProperty(UIEvents.EventTags.NEW_VALUE);
				String text = item.getText();
				boolean hasAsterisk = text.charAt(0) == '*';
				if (dirtyState.booleanValue()) {
					if (!hasAsterisk) {
						item.setText('*' + text);
					}
				} else if (hasAsterisk) {
					item.setText(text.substring(1));
				}
			}
		};
		eventBroker.subscribe(UIEvents.buildTopic(UIEvents.Dirtyable.TOPIC,
				UIEvents.Dirtyable.DIRTY), dirtyUpdater);
	}
	@PreDestroy
	public void contextDisposed() {
		super.contextDisposed(eventBroker);
		eventBroker.unsubscribe(itemUpdater);