diff --git a/ide/diffdialog.lfm b/ide/diffdialog.lfm
index f96d846828..6ee6cc4698 100644
--- a/ide/diffdialog.lfm
+++ b/ide/diffdialog.lfm
@@ -5,16 +5,16 @@ object DiffDlg: TDiffDlg
   Width = 598
   HelpType = htKeyword
   BorderIcons = [biSystemMenu]
-  Caption = 'Diff dialog'
+  Caption = 'Compare files'
   ClientHeight = 522
   ClientWidth = 598
   Position = poScreenCenter
-  LCLVersion = '0.9.31'
+  LCLVersion = '1.3'
   object Text1GroupBox: TGroupBox
     AnchorSideLeft.Control = Owner
     AnchorSideTop.Control = Owner
     Left = 6
-    Height = 53
+    Height = 57
     Top = 6
     Width = 586
     Align = alTop
@@ -22,7 +22,7 @@ object DiffDlg: TDiffDlg
     AutoSize = True
     BorderSpacing.Around = 6
     Caption = 'Text1GroupBox'
-    ClientHeight = 36
+    ClientHeight = 38
     ClientWidth = 582
     TabOrder = 0
     object Text1Combobox: TComboBox
@@ -30,9 +30,9 @@ object DiffDlg: TDiffDlg
       AnchorSideTop.Control = Text1GroupBox
       AnchorSideRight.Control = Text1FileOpenButton
       Left = 6
-      Height = 23
+      Height = 25
       Top = 6
-      Width = 316
+      Width = 320
       Anchors = [akTop, akLeft, akRight]
       BorderSpacing.Left = 6
       BorderSpacing.Top = 6
@@ -47,10 +47,10 @@ object DiffDlg: TDiffDlg
       AnchorSideTop.Side = asrCenter
       AnchorSideRight.Control = Text1GroupBox
       AnchorSideRight.Side = asrBottom
-      Left = 372
-      Height = 26
-      Top = 4
-      Width = 204
+      Left = 376
+      Height = 21
+      Top = 8
+      Width = 200
       Anchors = [akTop, akRight]
       BorderSpacing.Top = 6
       BorderSpacing.Right = 6
@@ -64,8 +64,8 @@ object DiffDlg: TDiffDlg
       AnchorSideRight.Control = Text1OnlySelectionCheckBox
       AnchorSideBottom.Control = Text1Combobox
       AnchorSideBottom.Side = asrBottom
-      Left = 328
-      Height = 23
+      Left = 332
+      Height = 25
       Top = 6
       Width = 32
       Anchors = [akTop, akRight, akBottom]
@@ -78,14 +78,14 @@ object DiffDlg: TDiffDlg
   object Text2GroupBox: TGroupBox
     AnchorSideTop.Control = Text1GroupBox
     Left = 6
-    Height = 53
-    Top = 65
+    Height = 57
+    Top = 69
     Width = 586
     Align = alTop
     AutoSize = True
     BorderSpacing.Around = 6
     Caption = 'Text2GroupBox'
-    ClientHeight = 36
+    ClientHeight = 38
     ClientWidth = 582
     TabOrder = 1
     object Text2Combobox: TComboBox
@@ -93,9 +93,9 @@ object DiffDlg: TDiffDlg
       AnchorSideTop.Control = Text2GroupBox
       AnchorSideRight.Control = Text2FileOpenButton
       Left = 6
-      Height = 23
+      Height = 25
       Top = 6
-      Width = 316
+      Width = 320
       Anchors = [akTop, akLeft, akRight]
       BorderSpacing.Left = 6
       BorderSpacing.Top = 6
@@ -110,10 +110,10 @@ object DiffDlg: TDiffDlg
       AnchorSideTop.Side = asrCenter
       AnchorSideRight.Control = Text2GroupBox
       AnchorSideRight.Side = asrBottom
-      Left = 372
-      Height = 26
-      Top = 4
-      Width = 204
+      Left = 376
+      Height = 21
+      Top = 8
+      Width = 200
       Anchors = [akTop, akRight]
       BorderSpacing.Top = 6
       BorderSpacing.Right = 6
@@ -127,8 +127,8 @@ object DiffDlg: TDiffDlg
       AnchorSideRight.Control = Text2OnlySelectionCheckBox
       AnchorSideBottom.Control = Text2Combobox
       AnchorSideBottom.Side = asrBottom
-      Left = 328
-      Height = 23
+      Left = 332
+      Height = 25
       Top = 6
       Width = 32
       Anchors = [akTop, akRight, akBottom]
@@ -147,7 +147,7 @@ object DiffDlg: TDiffDlg
     AnchorSideBottom.Control = ProgressBar1
     Left = 6
     Height = 109
-    Top = 345
+    Top = 344
     Width = 586
     Anchors = [akLeft, akRight, akBottom]
     AutoFill = True
@@ -170,8 +170,8 @@ object DiffDlg: TDiffDlg
     AnchorSideRight.Control = Owner
     AnchorSideBottom.Control = OptionsGroupBox
     Left = 6
-    Height = 215
-    Top = 124
+    Height = 206
+    Top = 132
     Width = 586
     Align = alTop
     BorderSpacing.Around = 6
@@ -189,50 +189,24 @@ object DiffDlg: TDiffDlg
     Gutter.Width = 55
     Gutter.MouseActions = <    
       item
-        Shift = []
-        ShiftMask = []
-        Button = mbLeft
         ClickCount = ccAny
         ClickDir = cdDown
-        Command = 13
-        MoveCaret = False
-        Option = 0
-        Priority = 0
+        Command = emcOnMainGutterClick
       end    
       item
-        Shift = []
-        ShiftMask = []
         Button = mbRight
-        ClickCount = ccSingle
-        ClickDir = cdUp
-        Command = 12
-        MoveCaret = False
-        Option = 0
-        Priority = 0
+        Command = emcContextMenu
       end>
     RightGutter.Width = 0
     RightGutter.MouseActions = <    
       item
-        Shift = []
-        ShiftMask = []
-        Button = mbLeft
         ClickCount = ccAny
         ClickDir = cdDown
-        Command = 13
-        MoveCaret = False
-        Option = 0
-        Priority = 0
+        Command = emcOnMainGutterClick
       end    
       item
-        Shift = []
-        ShiftMask = []
         Button = mbRight
-        ClickCount = ccSingle
-        ClickDir = cdUp
-        Command = 12
-        MoveCaret = False
-        Option = 0
-        Priority = 0
+        Command = emcContextMenu
       end>
     Highlighter = SynDiffSyn1
     Keystrokes = <    
@@ -558,141 +532,113 @@ object DiffDlg: TDiffDlg
       end>
     MouseActions = <    
       item
-        Shift = []
         ShiftMask = [ssShift, ssAlt]
-        Button = mbLeft
-        ClickCount = ccSingle
         ClickDir = cdDown
-        Command = 1
+        Command = emcStartSelections
         MoveCaret = True
-        Option = 0
-        Priority = 0
       end    
       item
         Shift = [ssShift]
         ShiftMask = [ssShift, ssAlt]
-        Button = mbLeft
-        ClickCount = ccSingle
         ClickDir = cdDown
-        Command = 1
+        Command = emcStartSelections
         MoveCaret = True
         Option = 1
-        Priority = 0
       end    
       item
         Shift = [ssAlt]
         ShiftMask = [ssShift, ssAlt]
-        Button = mbLeft
-        ClickCount = ccSingle
         ClickDir = cdDown
-        Command = 3
+        Command = emcStartColumnSelections
         MoveCaret = True
-        Option = 0
-        Priority = 0
       end    
       item
         Shift = [ssShift, ssAlt]
         ShiftMask = [ssShift, ssAlt]
-        Button = mbLeft
-        ClickCount = ccSingle
         ClickDir = cdDown
-        Command = 3
+        Command = emcStartColumnSelections
         MoveCaret = True
         Option = 1
-        Priority = 0
       end    
       item
-        Shift = []
-        ShiftMask = []
         Button = mbRight
-        ClickCount = ccSingle
-        ClickDir = cdUp
-        Command = 12
-        MoveCaret = False
-        Option = 0
-        Priority = 0
+        Command = emcContextMenu
       end    
       item
-        Shift = []
-        ShiftMask = []
-        Button = mbLeft
         ClickCount = ccDouble
         ClickDir = cdDown
-        Command = 6
+        Command = emcSelectWord
         MoveCaret = True
-        Option = 0
-        Priority = 0
       end    
       item
-        Shift = []
-        ShiftMask = []
-        Button = mbLeft
         ClickCount = ccTriple
         ClickDir = cdDown
-        Command = 7
+        Command = emcSelectLine
         MoveCaret = True
-        Option = 0
-        Priority = 0
       end    
       item
-        Shift = []
-        ShiftMask = []
-        Button = mbLeft
         ClickCount = ccQuad
         ClickDir = cdDown
-        Command = 8
+        Command = emcSelectPara
         MoveCaret = True
-        Option = 0
-        Priority = 0
       end    
       item
-        Shift = []
-        ShiftMask = []
         Button = mbMiddle
-        ClickCount = ccSingle
         ClickDir = cdDown
-        Command = 10
+        Command = emcPasteSelection
         MoveCaret = True
-        Option = 0
-        Priority = 0
       end    
       item
         Shift = [ssCtrl]
         ShiftMask = [ssShift, ssAlt, ssCtrl]
-        Button = mbLeft
-        ClickCount = ccSingle
-        ClickDir = cdUp
-        Command = 11
-        MoveCaret = False
-        Option = 0
-        Priority = 0
+        Command = emcMouseLink
       end>
+    MouseTextActions = <>
     MouseSelActions = <    
       item
-        Shift = []
-        ShiftMask = []
-        Button = mbLeft
-        ClickCount = ccSingle
         ClickDir = cdDown
-        Command = 9
-        MoveCaret = False
-        Option = 0
-        Priority = 0
+        Command = emcStartDragMove
       end>
     Lines.Strings = (
       'DiffSynEdit'
     )
     VisibleSpecialChars = [vscSpace, vscTabAtLast]
+    SelectedColor.FrameEdges = sfeAround
+    SelectedColor.BackPriority = 50
+    SelectedColor.ForePriority = 50
+    SelectedColor.FramePriority = 50
+    SelectedColor.BoldPriority = 50
+    SelectedColor.ItalicPriority = 50
+    SelectedColor.UnderlinePriority = 50
+    SelectedColor.StrikeOutPriority = 50
+    IncrementColor.FrameEdges = sfeAround
+    HighlightAllColor.FrameEdges = sfeAround
     BracketHighlightStyle = sbhsBoth
+    BracketMatchColor.Background = clNone
+    BracketMatchColor.Foreground = clNone
+    BracketMatchColor.FrameEdges = sfeAround
+    BracketMatchColor.Style = [fsBold]
+    FoldedCodeColor.Background = clNone
+    FoldedCodeColor.Foreground = clGray
+    FoldedCodeColor.FrameColor = clGray
+    FoldedCodeColor.FrameEdges = sfeAround
+    MouseLinkColor.Background = clNone
+    MouseLinkColor.Foreground = clBlue
+    MouseLinkColor.FrameEdges = sfeAround
+    LineHighlightColor.Background = clNone
+    LineHighlightColor.Foreground = clNone
+    LineHighlightColor.FrameEdges = sfeAround
     inline TSynGutterPartList
       object TSynGutterMarks
         Width = 24
+        MouseActions = <>
       end
       object TSynGutterLineNumber
         Width = 15
         MouseActions = <>
         MarkupInfo.Background = clBtnFace
         MarkupInfo.Foreground = clNone
+        MarkupInfo.FrameEdges = sfeAround
         DigitCount = 2
         ShowOnlyLineNumbersMultiplesOf = 1
         ZeroStart = False
@@ -700,35 +646,29 @@ object DiffDlg: TDiffDlg
       end
       object TSynGutterChanges
         Width = 4
+        MouseActions = <>
         ModifiedColor = 59900
         SavedColor = clGreen
       end
       object TSynGutterSeparator
         Width = 2
+        MouseActions = <>
+        MarkupInfo.Background = clWhite
+        MarkupInfo.Foreground = clGray
+        MarkupInfo.FrameEdges = sfeAround
       end
       object TSynGutterCodeFolding
         MouseActions = <        
           item
-            Shift = []
-            ShiftMask = []
             Button = mbRight
-            ClickCount = ccSingle
-            ClickDir = cdUp
-            Command = 16
-            MoveCaret = False
-            Option = 0
-            Priority = 0
+            Command = emcCodeFoldContextMenu
           end        
           item
-            Shift = []
             ShiftMask = [ssShift]
             Button = mbMiddle
             ClickCount = ccAny
             ClickDir = cdDown
-            Command = 14
-            MoveCaret = False
-            Option = 0
-            Priority = 0
+            Command = emcCodeFoldCollaps
           end        
           item
             Shift = [ssShift]
@@ -736,103 +676,65 @@ object DiffDlg: TDiffDlg
             Button = mbMiddle
             ClickCount = ccAny
             ClickDir = cdDown
-            Command = 14
-            MoveCaret = False
+            Command = emcCodeFoldCollaps
             Option = 1
-            Priority = 0
           end        
           item
-            Shift = []
-            ShiftMask = []
-            Button = mbLeft
             ClickCount = ccAny
             ClickDir = cdDown
-            Command = 0
-            MoveCaret = False
-            Option = 0
-            Priority = 0
+            Command = emcNone
           end>
         MarkupInfo.Background = clNone
         MarkupInfo.Foreground = clGray
+        MarkupInfo.FrameEdges = sfeAround
         MouseActionsExpanded = <        
           item
-            Shift = []
-            ShiftMask = []
-            Button = mbLeft
             ClickCount = ccAny
             ClickDir = cdDown
-            Command = 14
-            MoveCaret = False
-            Option = 0
-            Priority = 0
+            Command = emcCodeFoldCollaps
           end>
         MouseActionsCollapsed = <        
           item
             Shift = [ssCtrl]
             ShiftMask = [ssCtrl]
-            Button = mbLeft
             ClickCount = ccAny
             ClickDir = cdDown
-            Command = 15
-            MoveCaret = False
-            Option = 0
-            Priority = 0
+            Command = emcCodeFoldExpand
           end        
           item
-            Shift = []
             ShiftMask = [ssCtrl]
-            Button = mbLeft
             ClickCount = ccAny
             ClickDir = cdDown
-            Command = 15
-            MoveCaret = False
+            Command = emcCodeFoldExpand
             Option = 1
-            Priority = 0
           end>
       end
     end
   end
-  object SaveDiffButton: TBitBtn
+  object OpenInEditorButton: TBitBtn
     AnchorSideRight.Control = CloseButton
     AnchorSideBottom.Control = Owner
     AnchorSideBottom.Side = asrBottom
-    Left = 459
-    Height = 25
-    Top = 491
-    Width = 64
-    Anchors = [akRight, akBottom]
-    AutoSize = True
-    BorderSpacing.Around = 6
-    Caption = 'Save Diff'
-    NumGlyphs = 0
-    OnClick = SaveDiffButtonClick
-    TabOrder = 4
-  end
-  object OpenInEditorButton: TBitBtn
-    AnchorSideRight.Control = SaveDiffButton
-    AnchorSideBottom.Control = Owner
-    AnchorSideBottom.Side = asrBottom
-    Left = 320
-    Height = 25
-    Top = 491
-    Width = 133
+    Left = 373
+    Height = 26
+    Top = 490
+    Width = 137
     Anchors = [akRight, akBottom]
     AutoSize = True
     BorderSpacing.Around = 6
     Caption = 'OpenInEditorButton'
     ModalResult = 6
-    NumGlyphs = 0
-    TabOrder = 5
+    TabOrder = 4
   end
   object CloseButton: TBitBtn
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
     AnchorSideBottom.Control = Owner
     AnchorSideBottom.Side = asrBottom
-    Left = 529
-    Height = 26
-    Top = 490
-    Width = 63
+    Left = 516
+    Height = 27
+    Top = 489
+    Width = 76
     Anchors = [akRight, akBottom]
     AutoSize = True
     BorderSpacing.Around = 6
@@ -840,25 +742,23 @@ object DiffDlg: TDiffDlg
     Caption = '&Close'
     Kind = bkClose
     ModalResult = 2
-    NumGlyphs = 0
-    TabOrder = 6
+    TabOrder = 5
   end
   object HelpButton: TBitBtn
     AnchorSideLeft.Control = Owner
     AnchorSideBottom.Control = Owner
     AnchorSideBottom.Side = asrBottom
     Left = 6
-    Height = 26
-    Top = 490
-    Width = 57
+    Height = 33
+    Top = 483
+    Width = 76
     Anchors = [akLeft, akBottom]
     AutoSize = True
     BorderSpacing.Around = 6
     Caption = '&Help'
     Kind = bkHelp
-    NumGlyphs = 0
     OnClick = HelpButtonClick
-    TabOrder = 7
+    TabOrder = 6
   end
   object ProgressBar1: TProgressBar
     AnchorSideLeft.Control = Owner
@@ -867,36 +767,29 @@ object DiffDlg: TDiffDlg
     AnchorSideBottom.Control = CloseButton
     Left = 6
     Height = 24
-    Top = 460
-    Width = 466
+    Top = 459
+    Width = 462
     Anchors = [akLeft, akRight, akBottom]
     BorderSpacing.Around = 6
     Step = 0
-    TabOrder = 8
+    TabOrder = 7
   end
   object CancelScanningButton: TBitBtn
     AnchorSideTop.Control = ProgressBar1
     AnchorSideTop.Side = asrCenter
     AnchorSideRight.Control = Owner
     AnchorSideRight.Side = asrBottom
-    Left = 478
-    Height = 25
-    Top = 460
-    Width = 114
+    Left = 474
+    Height = 26
+    Top = 458
+    Width = 118
     Anchors = [akTop, akRight]
     AutoSize = True
     BorderSpacing.Around = 6
     Caption = 'Cancel Scanning'
     Enabled = False
     OnClick = CancelScanningButtonClick
-    TabOrder = 9
-  end
-  object dlgSave: TSaveDialog
-    DefaultExt = '.diff'
-    Filter = 'diff|*.diff|any file|*.*'
-    FilterIndex = 0
-    left = 272
-    top = 48
+    TabOrder = 8
   end
   object dlgOpen: TOpenDialog
     DefaultExt = '.pas'
diff --git a/ide/diffdialog.pas b/ide/diffdialog.pas
index df79264bce..058e4d28ec 100644
--- a/ide/diffdialog.pas
+++ b/ide/diffdialog.pas
@@ -28,7 +28,7 @@
   Author: Mattias Gaertner
   
   Abstract:
-    The TDiffDlg is the dialog for showing the differences between two files.
+    The TDiffDlg is a dialog for showing differences between two files.
 
 }
 
@@ -81,11 +81,9 @@ type
     DiffSynEdit: TSynEdit;
     OpenInEditorButton: TBitBtn;
     ProgressBar1: TProgressBar;
-    SaveDiffButton: TBitBtn;
     SynDiffSyn1: TSynDiffSyn;
     Text1FileOpenButton: TButton;
     CancelScanningButton: TBitBtn;
-    dlgSave: TSaveDialog;
     dlgOpen: TOpenDialog;
 
     Text2FileOpenButton: TButton;
@@ -107,7 +105,6 @@ type
     procedure FileOpenClick(Sender: TObject);
     procedure HelpButtonClick(Sender: TObject);
     procedure OnChangeFlag(Sender: TObject);
-    procedure SaveDiffButtonClick(Sender: TObject);
     procedure Text1ComboboxChange(Sender: TObject);
     procedure Text2ComboboxChange(Sender: TObject);
   private
@@ -135,8 +132,7 @@ type
     property IdleConnected: boolean read fIdleConnected write SetIdleConnected;
   end;
   
-function ShowDiffDialog(Text1Index: integer;
-  var OpenDiffInEditor: boolean; var Diff: string): TModalResult;
+function ShowDiffDialog(Text1Index: integer; out Diff: string): TModalResult;
 
 const
   IgnoreCaseCheckBox = 0;
@@ -151,36 +147,33 @@ implementation
 
 {$R *.lfm}
 
-function ShowDiffDialog(Text1Index: integer;
-  var OpenDiffInEditor: boolean; var Diff: string): TModalResult;
+function ShowDiffDialog(Text1Index: integer; out Diff: string): TModalResult;
 var
   DiffDlg: TDiffDlg;
   Files: TDiffFiles;
   i: Integer;
   SrcEdit: TSourceEditor;
 begin
+  DiffDlg := TDiffDlg.Create(nil);
   Files := TDiffFiles.Create;
-  for i:=0 to SourceEditorManager.SourceEditorCount - 1 do begin
-    SrcEdit := SourceEditorManager.SourceEditors[i]; // FindSourceEditorWithPageIndex(i);
-    Files.Add(TDiffFile.Create(SrcEdit.PageName, SrcEdit, SrcEdit.SelectionAvailable));
+  try
+    // Get available files
+    for i:=0 to SourceEditorManager.SourceEditorCount - 1 do begin
+      SrcEdit := SourceEditorManager.SourceEditors[i]; // FindSourceEditorWithPageIndex(i);
+      Files.Add(TDiffFile.Create(SrcEdit.PageName, SrcEdit, SrcEdit.SelectionAvailable));
+    end;
+    DiffDlg.Files := Files;
+    DiffDlg.SetText1Index(Text1Index);
+    DiffDlg.Init;
+    Result := DiffDlg.ShowModal;
+    DiffDlg.SaveSettings;
+    // "Open in editor" button returns mrYes.
+    if Result=mrYes then
+      Diff := DiffDlg.DiffSynEdit.Text;
+  finally
+    Files.Free;
+    DiffDlg.Free;
   end;
-
-  OpenDiffInEditor:=false;
-  DiffDlg:=TDiffDlg.Create(nil);
-  DiffDlg.Files:=Files;
-  DiffDlg.SetText1Index(Text1Index);
-  DiffDlg.Init;
-  Result:=DiffDlg.ShowModal;
-  DiffDlg.SaveSettings;
-
-  if Result=mrYes then begin
-    OpenDiffInEditor:=true;
-    Diff:=DiffDlg.DiffSynEdit.Text;
-    Result:=mrOk;
-  end;
-
-  Files.Free;
-  DiffDlg.Free;
 end;
 
 { TDiffDlg }
@@ -228,16 +221,6 @@ begin
   LazarusHelp.ShowHelpForIDEControl(Self);
 end;
 
-procedure TDiffDlg.SaveDiffButtonClick(Sender: TObject);
-begin
-  if dlgSave.Execute then begin
-    try
-      SaveStringsToFileUTF8(DiffSynEdit.Lines,dlgSave.FileName);
-    except
-    end;
-  end;
-end;
-
 procedure TDiffDlg.Text1ComboboxChange(Sender: TObject);
 begin
   SetText1Index(Text1Combobox.Items.IndexOf(Text1Combobox.Text));
@@ -251,12 +234,12 @@ end;
 procedure TDiffDlg.SetupComponents;
 begin
   // text 1
-  Text1GroupBox.Caption:=lisDiffDlgText1;
+  Text1GroupBox.Caption:=lisDiffDlgFile1;
   Text1OnlySelectionCheckBox.Caption:=lisDiffDlgOnlySelection;
   Text1FileOpenButton.Caption:='...';
 
   // text 2
-  Text2GroupBox.Caption:=lisDiffDlgText2;
+  Text2GroupBox.Caption:=lisDiffDlgFile2;
   Text2OnlySelectionCheckBox.Caption:=lisDiffDlgOnlySelection;
   Text2FileOpenButton.Caption:='...';
 
@@ -277,17 +260,12 @@ begin
   CancelScanningButton.LoadGlyphFromResourceName(hInstance, 'btn_cancel');
   CloseButton.Caption:=lisClose;
   OpenInEditorButton.Caption:=lisDiffDlgOpenDiffInEditor;
-  SaveDiffButton.Caption:=lisDlgSave;
   HelpButton.Caption:=lisMenuHelp;
 
   OpenInEditorButton.LoadGlyphFromStock(idButtonOpen);
   if OpenInEditorButton.Glyph.Empty then
     OpenInEditorButton.LoadGlyphFromResourceName(HInstance, 'laz_open');
   
-  SaveDiffButton.LoadGlyphFromStock(idButtonSave);
-  if SaveDiffButton.Glyph.Empty then
-    SaveDiffButton.LoadGlyphFromResourceName(HInstance, 'laz_save');
-
   // dialogs
   dlgOpen.Title:=lisOpenExistingFile;
   dlgOpen.Filter:=dlgAllFiles+' ('+GetAllFilesMask+')|'+GetAllFilesMask
@@ -296,8 +274,6 @@ begin
                  +'|'+lisLazarusForm+' (*.lfm;*.dfm)|*.lfm;*.dfm'
                  +'|'+lisLazarusPackage+' (*.lpk)|*.lpk'
                  +'|'+lisLazarusProjectSource+' (*.lpr)|*.lpr';
-  dlgSave.Title:=lisSaveFileAs;
-  dlgSave.Filter:=dlgAllFiles+' ('+GetAllFilesMask+')|'+GetAllFilesMask;
 
   // diff
   EditorOpts.GetSynEditSettings(DiffSynEdit);
@@ -360,7 +336,6 @@ begin
     Text1GroupBox.Enabled := False;
     Text2GroupBox.Enabled := False;
     OpenInEditorButton.Enabled := False;
-    SaveDiffButton.Enabled := False;
     //CancelScanningButton.Enabled := True;
 
     DiffOutput:=TDiffOutput.Create(Text1Src, Text2Src, GetDiffOptions, ProgressBar1);
@@ -371,7 +346,6 @@ begin
     end;
 
     //CancelScanningButton.Enabled := False;
-    SaveDiffButton.Enabled := True;
     OpenInEditorButton.Enabled := True;
     Text2GroupBox.Enabled := True;
     Text1GroupBox.Enabled := True;
@@ -384,7 +358,7 @@ begin
   inherited Create(TheOwner);
   fUpdating := False;
   fCancelled := False;
-  Caption := lisCaptionDiff;
+  Caption := lisCaptionCompareFiles;
   IDEDialogLayoutList.ApplyLayout(Self,600,500);
   SetupComponents;
 end;
diff --git a/ide/lazarusidestrconsts.pas b/ide/lazarusidestrconsts.pas
index 397fed3a74..6b5ff8f7fe 100644
--- a/ide/lazarusidestrconsts.pas
+++ b/ide/lazarusidestrconsts.pas
@@ -511,8 +511,8 @@ resourcestring
   lisMenuGuessUnclosedBlock = 'Guess Unclosed Block';
   lisMenuGuessMisplacedIFDEF = 'Guess Misplaced IFDEF/ENDIF';
   lisMenuMakeResourceString = 'Make Resource String ...';
-  lisCaptionDiff = 'Diff';
-  lisMenuDiff = 'Diff ...';
+  lisCaptionCompareFiles = 'Compare files (not for creating patches)';
+  lisMenuCompareFiles = 'Compare files ...';
   lisMenuConvertDFMtoLFM = 'Convert Binary DFM to Text LFM + Check Syntax ...';
   lisMenuCheckLFM = 'Check LFM File in Editor';
   lisMenuDelphiConversion = 'Delphi Conversion';
@@ -3398,9 +3398,9 @@ resourcestring
   lisTheApplicationBundleWasCreatedFor = 'The Application Bundle was created for "%s"';
 
   // diff dialog
-  lisDiffDlgText1 = 'Text1';
+  lisDiffDlgFile1 = 'File1';
   lisDiffDlgOnlySelection = 'Only selection';
-  lisDiffDlgText2 = 'Text2';
+  lisDiffDlgFile2 = 'File2';
   lisDiffDlgCaseInsensitive = 'Case Insensitive';
   lisDiffDlgIgnoreIfEmptyLinesWereAdd = 'Ignore if empty lines were added or removed';
   lisDiffDlgIgnoreSpacesAtStartOfLine = 'Ignore spaces at start of line';
@@ -3409,7 +3409,7 @@ resourcestring
     +'g. #10 = #13#10)';
   lisDiffDlgIgnoreIfSpaceCharsWereAdd = 'Ignore amount of space chars';
   lisDiffDlgIgnoreSpaces = 'Ignore spaces (newline chars not included)';
-  lisDiffDlgOpenDiffInEditor = 'Open Diff in editor';
+  lisDiffDlgOpenDiffInEditor = 'Open difference in editor';
 
   // packages
   lisPkgFileTypeUnit = 'Unit';
diff --git a/ide/main.pp b/ide/main.pp
index 5357bf3477..38431b3baf 100644
--- a/ide/main.pp
+++ b/ide/main.pp
@@ -9928,7 +9928,6 @@ function TMainIDE.DoDiff: TModalResult;
 var
   ActiveSrcEdit: TSourceEditor;
   ActiveUnitInfo: TUnitInfo;
-  OpenDiffInEditor: boolean;
   DiffText: string;
   NewDiffFilename: String;
 begin
@@ -9936,10 +9935,9 @@ begin
   GetCurrentUnit(ActiveSrcEdit,ActiveUnitInfo);
   if ActiveSrcEdit=nil then exit;
 
-  Result:=ShowDiffDialog(ActiveSrcEdit.PageIndex,
-                         OpenDiffInEditor,DiffText);
-  if OpenDiffInEditor then begin
-    NewDiffFilename:=CreateSrcEditPageName('','diff.txt', nil);
+  Result:=ShowDiffDialog(ActiveSrcEdit.PageIndex, DiffText);
+  if Result = mrYes then begin
+    NewDiffFilename:=CreateSrcEditPageName('','FileDifference.diff', nil);
     Result:=DoNewEditorFile(FileDescriptorText,NewDiffFilename,DiffText,
                             [nfOpenInEditor]);
     GetCurrentUnit(ActiveSrcEdit,ActiveUnitInfo);
diff --git a/ide/mainbase.pas b/ide/mainbase.pas
index 66028d851e..78e529f890 100644
--- a/ide/mainbase.pas
+++ b/ide/mainbase.pas
@@ -997,7 +997,7 @@ begin
     CreateMenuSeparatorSection(mnuTools,itmSecondaryTools,'itmSecondaryTools');
     ParentMI:=itmSecondaryTools;
     CreateMenuItem(ParentMI,itmToolManageExamples,'itmToolManageExamples',lisMenuExampleProjects, 'camera');
-    CreateMenuItem(ParentMI,itmToolDiff,'itmToolDiff',lisMenuDiff, 'menu_tool_diff');
+    CreateMenuItem(ParentMI,itmToolDiff,'itmToolDiff',lisMenuCompareFiles, 'menu_tool_diff');
 
     CreateMenuSubSection(mnuTools,itmDelphiConversion,'itmDelphiConversion',lisMenuDelphiConversion,'menu_tool_dfm_to_lfm');
     ParentMI:=itmDelphiConversion;