diff --git a/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/actions/IpnbMoveCellDownAction.java b/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/actions/IpnbMoveCellDownAction.java
index 924891372ce5..123cfb46e7d1 100644
--- a/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/actions/IpnbMoveCellDownAction.java
+++ b/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/actions/IpnbMoveCellDownAction.java
@@ -24,7 +24,6 @@ public class IpnbMoveCellDownAction extends AnAction {
           ApplicationManager.getApplication().runWriteAction(new Runnable() {
             public void run() {
               ipnbFilePanel.moveCell(true);
-              ipnbFilePanel.saveToFile();
             }
           });
         }
diff --git a/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/actions/IpnbMoveCellUpAction.java b/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/actions/IpnbMoveCellUpAction.java
index e3df036a5040..026e663d3a00 100644
--- a/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/actions/IpnbMoveCellUpAction.java
+++ b/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/actions/IpnbMoveCellUpAction.java
@@ -24,7 +24,6 @@ public class IpnbMoveCellUpAction extends AnAction {
           ApplicationManager.getApplication().runWriteAction(new Runnable() {
             public void run() {
               ipnbFilePanel.moveCell(false);
-              ipnbFilePanel.saveToFile();
             }
           });
         }
diff --git a/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/panels/IpnbFilePanel.java b/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/panels/IpnbFilePanel.java
index 0de2d5795688..77922d5ac5f7 100644
--- a/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/panels/IpnbFilePanel.java
+++ b/python/ipnb/src/org/jetbrains/plugins/ipnb/editor/panels/IpnbFilePanel.java
@@ -224,6 +224,8 @@ public class IpnbFilePanel extends JPanel implements Scrollable, DataProvider, D
       addCell(siblingPanel, true);
       setSelectedCell(selectedCell);
     }
+    saveToFile();
+
   }
 
   public void deleteSelectedCell() {
@@ -248,6 +250,11 @@ public class IpnbFilePanel extends JPanel implements Scrollable, DataProvider, D
   public void saveToFile() {
     final String oldText = myDocument.getText();
     final String newText = IpnbParser.newDocumentText(this);
+    if (newText == null) return;
+    if (oldText.equals(newText)) {
+      new Alarm().addRequest(new MySynchronizeRequest(), 10, ModalityState.stateForComponent(this));
+      return;
+    }
     try {
       final ReplaceInfo replaceInfo = findFragmentToChange(oldText, newText);
       if (replaceInfo.getStartOffset() != -1) {
@@ -283,7 +290,7 @@ public class IpnbFilePanel extends JPanel implements Scrollable, DataProvider, D
     }
   }
 
-  public static ReplaceInfo findFragmentToChange(final String oldText, final String newText) {
+  public static ReplaceInfo findFragmentToChange(@NotNull final String oldText, @NotNull final String newText) {
     if (oldText.equals(newText)) {
       return new ReplaceInfo(-1, -1, null);
     }
diff --git a/python/ipnb/src/org/jetbrains/plugins/ipnb/format/IpnbParser.java b/python/ipnb/src/org/jetbrains/plugins/ipnb/format/IpnbParser.java
index d6b66beda5ec..b9c48ebfe8ab 100644
--- a/python/ipnb/src/org/jetbrains/plugins/ipnb/format/IpnbParser.java
+++ b/python/ipnb/src/org/jetbrains/plugins/ipnb/format/IpnbParser.java
@@ -9,6 +9,7 @@ import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.Document;
 import com.intellij.openapi.util.text.StringUtil;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 import org.jetbrains.plugins.ipnb.editor.panels.IpnbEditablePanel;
 import org.jetbrains.plugins.ipnb.editor.panels.IpnbFilePanel;
 import org.jetbrains.plugins.ipnb.format.cells.*;
@@ -66,6 +67,7 @@ public class IpnbParser {
     writeToFile(ipnbPanel.getIpnbFile().getPath(), json);
   }
 
+  @Nullable
   public static String newDocumentText(@NotNull final IpnbFilePanel ipnbPanel) {
     final IpnbFile ipnbFile = ipnbPanel.getIpnbFile();
     if (ipnbFile == null) return null;