It's actually first time I had to make a custom part of GUI extensible. In an Eclipse forms editor like following, we wanted custom actions to come from various plugins: Since eclipse APIs provides this sort of extensibility with their org.eclipse.ui.menus extension point, I looked at how to reuse that mechanism. It turns simple. All you need to do is, while creating the editable area, add: final Composite parent = ... // that's the area we want to make extensible ContributionManager contributionManager = new ContributionManager() { public void update(boolean force) { for (IContributionItem item : items) { item.fill(parent); } } }; IMenuService service = (IMenuService) getSite().getService(IMenuService.class); contributionManager.add(new GroupMarker("testing")); service.populateContributionManager(contributionManager, "toolbar:org.zend.editor1?after=testing"); contributionManager.update(false); Now to contribute something to that area, you ...