diff --git a/plugins/org.eclipse.fordiac.ide.application/src/org/eclipse/fordiac/ide/application/handlers/OpenTypeHandler.java b/plugins/org.eclipse.fordiac.ide.application/src/org/eclipse/fordiac/ide/application/handlers/OpenTypeHandler.java
index 7e5b3b9dc3..6618bd3c65 100644
--- a/plugins/org.eclipse.fordiac.ide.application/src/org/eclipse/fordiac/ide/application/handlers/OpenTypeHandler.java
+++ b/plugins/org.eclipse.fordiac.ide.application/src/org/eclipse/fordiac/ide/application/handlers/OpenTypeHandler.java
@@ -12,50 +12,54 @@
  *******************************************************************************/
 package org.eclipse.fordiac.ide.application.handlers;
 
+import java.util.ArrayList;
+import java.util.List;
+
 import org.eclipse.core.commands.AbstractHandler;
 import org.eclipse.core.commands.ExecutionEvent;
 import org.eclipse.core.commands.ExecutionException;
-import org.eclipse.core.resources.IFile;
-import org.eclipse.core.runtime.Status;
+import org.eclipse.emf.ecore.EObject;
 import org.eclipse.fordiac.ide.model.libraryElement.FBNetwork;
 import org.eclipse.fordiac.ide.model.libraryElement.FBNetworkElement;
 import org.eclipse.fordiac.ide.model.libraryElement.IInterfaceElement;
-import org.eclipse.fordiac.ide.model.libraryElement.LibraryElement;
+import org.eclipse.fordiac.ide.model.libraryElement.INamedElement;
+import org.eclipse.fordiac.ide.model.libraryElement.SubApp;
+import org.eclipse.fordiac.ide.model.libraryElement.SubAppType;
+import org.eclipse.fordiac.ide.model.libraryElement.TypedSubApp;
+import org.eclipse.fordiac.ide.model.libraryElement.UntypedSubApp;
+import org.eclipse.fordiac.ide.model.ui.actions.OpenListenerManager;
 import org.eclipse.fordiac.ide.ui.FordiacLogHelper;
 import org.eclipse.gef.EditPart;
 import org.eclipse.jface.viewers.ISelection;
 import org.eclipse.jface.viewers.IStructuredSelection;
-import org.eclipse.ui.IEditorDescriptor;
 import org.eclipse.ui.ISources;
 import org.eclipse.ui.IWorkbench;
-import org.eclipse.ui.IWorkbenchPage;
 import org.eclipse.ui.IWorkbenchWindow;
 import org.eclipse.ui.PlatformUI;
 import org.eclipse.ui.handlers.HandlerUtil;
-import org.eclipse.ui.part.FileEditorInput;
 
 public class OpenTypeHandler extends AbstractHandler {
 
 	@Override
 	public Object execute(final ExecutionEvent event) throws ExecutionException {
+
 		final IStructuredSelection sel = HandlerUtil.getCurrentStructuredSelection(event);
-		final IFile typeFile = getSelectedTypeFile(sel);
-		if (typeFile != null) {
-			openTypeEditor(typeFile);
+		final EObject type = getTypeFromSelection(sel);
+
+		if (type != null) {
+			openTypeEditor(type);
 		}
-		return Status.OK_STATUS;
+
+		return null;
 	}
 
-	private static void openTypeEditor(final IFile file) {
+	private static void openTypeEditor(final EObject type) {
 		final IWorkbench workbench = PlatformUI.getWorkbench();
-		if (null != workbench) {
+		if (workbench != null) {
 			final IWorkbenchWindow activeWorkbenchWindow = workbench.getActiveWorkbenchWindow();
-			if (null != activeWorkbenchWindow) {
-				final IWorkbenchPage activePage = activeWorkbenchWindow.getActivePage();
-				final IEditorDescriptor desc = PlatformUI.getWorkbench().getEditorRegistry()
-						.getDefaultEditor(file.getName());
+			if (activeWorkbenchWindow != null) {
 				try {
-					activePage.openEditor(new FileEditorInput(file), desc.getId());
+					OpenListenerManager.openEditor(type);
 				} catch (final Exception e) {
 					FordiacLogHelper.logError(e.getMessage(), e);
 				}
@@ -67,32 +71,55 @@ private static void openTypeEditor(final IFile file) {
 	public void setEnabled(final Object evaluationContext) {
 		final ISelection sel = (ISelection) HandlerUtil.getVariable(evaluationContext,
 				ISources.ACTIVE_CURRENT_SELECTION_NAME);
-		setBaseEnabled(getSelectedTypeFile(sel) != null);
+
+		setBaseEnabled(getTypeFromSelection(sel) != null);
 	}
 
-	private static IFile getSelectedTypeFile(final ISelection sel) {
+	private static EObject getTypeFromSelection(final ISelection sel) {
 		if ((sel instanceof final IStructuredSelection structSel) && !sel.isEmpty() && (structSel.size() == 1)) {
 			Object obj = structSel.getFirstElement();
+
 			if (obj instanceof final EditPart ep) {
 				obj = ep.getModel();
 			}
 
-			final LibraryElement type = switch (obj) {
+			final EObject type = switch (obj) {
 			case final FBNetwork fbn -> getTypeFromFbn(fbn);
 			case final FBNetworkElement fbnEl -> fbnEl.getType();
 			case final IInterfaceElement ie -> ie.getType();
 			default -> null;
 			};
 
-			if ((type != null) && (type.getTypeEntry() != null)) {
-				return type.getTypeEntry().getFile();
+			if ((type != null)) {
+				return type;
 			}
 		}
 
 		return null;
 	}
 
-	private static LibraryElement getTypeFromFbn(final FBNetwork fbn) {
+	private static EObject getTypeFromFbn(final FBNetwork fbn) {
+
+		if (fbn.eContainer() instanceof final UntypedSubApp usa) {
+			EObject element = usa;
+
+			final List<String> subApps = new ArrayList<>();
+
+			while (element != null) {
+				if (element instanceof final INamedElement ine) {
+					subApps.add(ine.getName());
+				}
+
+				if (element.eContainer() instanceof final TypedSubApp tsa) {
+					subApps.add(tsa.getName());
+
+					return getEObjectFromString(subApps, tsa.getType());
+				}
+
+				element = element.eContainer();
+			}
+		}
+
 		if (fbn.eContainer() instanceof final FBNetworkElement fbne) {
 			return fbne.getType();
 		}
@@ -100,4 +127,20 @@ private static LibraryElement getTypeFromFbn(final FBNetwork fbn) {
 		return null;
 	}
 
+	private static SubApp getEObjectFromString(final List<String> subApps, final SubAppType type) {
+		FBNetwork fb = type.getFBNetwork();
+		SubApp last = null;
+
+		for (final String s : subApps.reversed()) {
+			final SubApp sa = fb.getSubAppNamed(s);
+
+			if (sa != null) {
+				last = sa;
+				fb = sa.getSubAppNetwork();
+			}
+		}
+
+		return last;
+	}
+
 }