Bug 57454 "show intro" preference not saved until shutdown
M8 As a general rule of thumb, if a plug-in changes a preference value then it should save it immediately. (or when the user hits OK/Apply in the prefs page, etc etc) When you start M8 and close the Intro page, I noticed that the ui.ide preferences are not saved until the workbench is shutdown.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/IDEWorkbenchAdvisor.java
initializeFeatureSets();
		Set s = getNewlyAddedFeatures();
		welcomePerspectiveInfos = new ArrayList(s.size());
		for (Iterator it = s.iterator(); it.hasNext(); ) {
			String versionedId = (String) it.next();
			String featureId = versionedId.substring(0, versionedId.indexOf(':'));
			String featureVersionId = versionedId.substring(versionedId.indexOf(':')+1);
			AboutInfo info = AboutInfo.readFeatureInfo(featureId, featureVersionId, featureId);
			if (info != null && info.getWelcomePerspectiveId() != null && info.getWelcomePageURL() != null) {
				welcomePerspectiveInfos.add(info);
			}
		}
	}
	/* (non-Javadoc)
	 * @see org.eclipse.ui.application.WorkbenchAdvisor#postStartup()
	 */
	public void postStartup() {
		refreshFromLocal();
				
		checkUpdates();
	}
	/* (non-Javadoc)
	 * @see org.eclipse.ui.application.WorkbenchAdvisor#postShutdown
	 */
	public void postShutdown() {
		if (activityHelper != null) {
			activityHelper.shutdown();
			activityHelper = null;
		}