Bug 284675 [Compatibility] background editor appears to get commands
After a while and an undetermined set of steps, commands executed (like cut, copy, paste, content assist) don't do anything in the "active" editor but effect a previous editor. Due to the way the lookup currently works, it is mostly likely caused by the change to that editor is not updating the IEclipseContext ACTIVE_CHILD (so the commands are being retrieved from the previous editor). PW
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/workbench/ui/internal/Activator.java
/**
	 * The bundle symbolic name.
	 */
	public static final String PI_WORKBENCH = "org.eclipse.e4.ui.workbench"; 
	private static Activator activator;
	private BundleContext context;
	private ServiceRegistration executorTracker;
	private ServiceTracker locationTracker;
	private ServiceTracker pkgAdminTracker;
	private ServiceTracker debugTracker;