diff --git a/key.core/src/main/java/de/uka/ilkd/key/taclettranslation/lemma/EmptyEnvInput.java b/key.core/src/main/java/de/uka/ilkd/key/taclettranslation/lemma/EmptyEnvInput.java
index 74338e792e6..2c2d47deed2 100644
--- a/key.core/src/main/java/de/uka/ilkd/key/taclettranslation/lemma/EmptyEnvInput.java
+++ b/key.core/src/main/java/de/uka/ilkd/key/taclettranslation/lemma/EmptyEnvInput.java
@@ -11,6 +11,7 @@
 import de.uka.ilkd.key.proof.io.AbstractEnvInput;
 import de.uka.ilkd.key.speclang.PositionedString;
 
+import org.key_project.util.collection.DefaultImmutableSet;
 import org.key_project.util.collection.ImmutableSet;
 
 public class EmptyEnvInput extends AbstractEnvInput {
@@ -21,8 +22,7 @@ public EmptyEnvInput(Profile profile) {
 
     @Override
     public ImmutableSet<PositionedString> read() throws ProofInputException {
-        // nothing to to do
-        return null;
+        return DefaultImmutableSet.nil();
     }
 
     @Override
diff --git a/key.ui/src/main/java/de/uka/ilkd/key/gui/actions/LemmaGenerationAction.java b/key.ui/src/main/java/de/uka/ilkd/key/gui/actions/LemmaGenerationAction.java
index cf1fc6ae46b..a47a606203b 100644
--- a/key.ui/src/main/java/de/uka/ilkd/key/gui/actions/LemmaGenerationAction.java
+++ b/key.ui/src/main/java/de/uka/ilkd/key/gui/actions/LemmaGenerationAction.java
@@ -233,6 +233,7 @@ public void doStopped(ProofAggregate p, ImmutableSet<Taclet> taclets,
                     getMediator().startInterface(true);
                     if (p != null) {
                         mainWindow.getUserInterface().registerProofAggregate(p);
+                        mainWindow.getMediator().getSelectionModel().setSelectedProof(p.getFirstProof());
                     }
                 }