diff --git a/src/com/jpexs/decompiler/flash/gui/abc/ABCPanel.java b/src/com/jpexs/decompiler/flash/gui/abc/ABCPanel.java
index e019007c6..0a42fcb18 100644
--- a/src/com/jpexs/decompiler/flash/gui/abc/ABCPanel.java
+++ b/src/com/jpexs/decompiler/flash/gui/abc/ABCPanel.java
@@ -228,6 +228,7 @@ public class ABCPanel extends JPanel implements ItemListener, SearchListener<ABC
 
     public void setAbc(ABC abc) {
         this.abc = abc;
+        setDecompiledEditMode(false);
         navigator.setAbc(abc);
         updateConstList();
     }
@@ -629,7 +630,11 @@ public class ABCPanel extends JPanel implements ItemListener, SearchListener<ABC
 
     public void reload() {
         lastDecompiled = "";
-        getSwf().clearScriptCache();
+        SWF swf = getSwf();
+        if (swf != null) {
+            swf.clearScriptCache();
+        }
+
         decompiledTextArea.reloadClass();
         detailPanel.methodTraitPanel.methodCodePanel.clear();
     }
@@ -760,12 +765,13 @@ public class ABCPanel extends JPanel implements ItemListener, SearchListener<ABC
             String as = decompiledTextArea.getText();
             abc.replaceScriptPack(pack, as);
             lastDecompiled = as;
+            setDecompiledEditMode(false);
             mainPanel.updateClassesList();
 
             if (oldSp != null) {
                 hilightScript(getSwf(), oldSp);
             }
-            setDecompiledEditMode(false);
+
             reload();
             View.showMessageDialog(this, AppStrings.translate("message.action.saved"), AppStrings.translate("dialog.message.title"), JOptionPane.INFORMATION_MESSAGE, Configuration.showCodeSavedMessage);
         } catch (AVM2ParseException ex) {
diff --git a/src/com/jpexs/decompiler/flash/gui/abc/ClassesListTreeModel.java b/src/com/jpexs/decompiler/flash/gui/abc/ClassesListTreeModel.java
index 9aa967e75..64b7d95fa 100644
--- a/src/com/jpexs/decompiler/flash/gui/abc/ClassesListTreeModel.java
+++ b/src/com/jpexs/decompiler/flash/gui/abc/ClassesListTreeModel.java
@@ -46,15 +46,11 @@ public class ClassesListTreeModel extends AS3ClassTreeItem implements TreeModel
     }
 
     public ClassesListTreeModel(SWF swf) {
-        this(swf, null);
-    }
-
-    public ClassesListTreeModel(SWF swf, String filter) {
         super(null, null);
         root = new AS3Package(null, swf);
         this.swf = swf;
         this.list = swf.getAS3Packs();
-        setFilter(filter);
+        setFilter(null);
     }
 
     @Override
@@ -191,4 +187,18 @@ public class ClassesListTreeModel extends AS3ClassTreeItem implements TreeModel
     public boolean isModified() {
         return root.isModified();
     }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (!(obj instanceof ClassesListTreeModel)) {
+            return false;
+        }
+
+        return swf.equals(((ClassesListTreeModel) obj).swf);
+    }
+
+    @Override
+    public int hashCode() {
+        return ClassesListTreeModel.class.hashCode() ^ swf.hashCode();
+    }
 }
diff --git a/src/com/jpexs/decompiler/flash/gui/editor/UndoFixedEditorPane.java b/src/com/jpexs/decompiler/flash/gui/editor/UndoFixedEditorPane.java
index b509983b3..e43e1cc8a 100644
--- a/src/com/jpexs/decompiler/flash/gui/editor/UndoFixedEditorPane.java
+++ b/src/com/jpexs/decompiler/flash/gui/editor/UndoFixedEditorPane.java
@@ -102,6 +102,10 @@ public class UndoFixedEditorPane extends JEditorPane {
 
     private void setText(String t, String contentType) {
         synchronized (setTextLock) {
+            if (t == null) {
+                t = "";
+            }
+
             if (!t.equals(getText())) {
                 boolean plain = t.length() > Configuration.syntaxHighlightLimit.get();
                 if (plain) {