diff --git a/src/Edit.c b/src/Edit.c
index 3d795fd70..b081acfce 100644
--- a/src/Edit.c
+++ b/src/Edit.c
@@ -570,8 +570,8 @@ bool EditIsRecodingNeeded(WCHAR* pszText, int cchLen)
 //
 //  EditGetClipboardText()
 //
-char* EditGetClipboardText(HWND hwnd,bool bCheckEncoding,int* pLineCount,int* pLenLastLn) {
-
+char* EditGetClipboardText(HWND hwnd, bool bCheckEncoding, int* pLineCount, int* pLenLastLn) 
+{
   if (!IsClipboardFormatAvailable(CF_UNICODETEXT) || !OpenClipboard(GetParent(hwnd))) {
     char* pEmpty = StrDupA("");
     return (pEmpty);
@@ -613,7 +613,9 @@ char* EditGetClipboardText(HWND hwnd,bool bCheckEncoding,int* pLineCount,int* pL
 
   int lineCount = 0;
   int lenLastLine = 0;
-  if ((bool)SendMessage(hwnd,SCI_GETPASTECONVERTENDINGS,0,0)) {
+
+  if ((bool)SendMessage(hwnd,SCI_GETPASTECONVERTENDINGS,0,0)) 
+  {
     char* ptmp = LocalAlloc(LPTR,mlen * 2 + 2);
     if (ptmp) {
       char *s = pmch;
@@ -731,177 +733,47 @@ bool EditClearClipboard(HWND hwnd)
 
 //=============================================================================
 //
-//  EditPaste2RectSel()
+//  EditSwapClipboard()
 //
-void EditPaste2RectSel(HWND hwnd, char* pText)
-{
-  if (!SciCall_IsSelectionRectangle()) { return; }
-
-  const DocPos length = lstrlenA(pText); // '\0' terminated
-
-  _IGNORE_NOTIFY_CHANGE_;
-  _ENTER_TARGET_TRANSACTION_;
-
-  const DocPosU selCount = (DocPosU)SendMessage(hwnd, SCI_GETSELECTIONS, 0, 0);
-
-  char* pTextLine = pText;
-  // remove line-break from last line
-  if (*pTextLine != '\0') { StrTrimA(pTextLine, "\r\n"); }
-
-  for (DocPosU s = 0; s < selCount; ++s) {
-    // get lines from clip
-    char *ln = pTextLine;
-    int lnLen = 0;
-    while (*ln != '\0') {
-      if (s < (selCount - 1)) {
-        if (*ln == '\n' || *ln == '\r') {
-          if ((*ln == '\r') && (*(ln + 1) == '\n')) { ++ln; }
-          ++ln; // next line
-          break;
-        }
-        else { ++ln; ++lnLen; }
-      }
-      else { ++ln; ++lnLen; } // last line
-    }
-
-    const DocPos selCaretPos = SciCall_GetSelectionNCaret(s);
-    const DocPos selAnchorPos = SciCall_GetSelectionNAnchor(s);
-    const DocPos selCaretVspc = SciCall_GetSelectionNCaretVirtualSpace(s);
-    const DocPos selAnchorVspc = SciCall_GetSelectionNAnchorVirtualSpace(s);
-
-    DocPos virtualSpaceLen = 0;
-    DocPos selTargetStart = 0;
-    DocPos selTargetEnd = 0;
-    if (selCaretPos < selAnchorPos) {
-      selTargetStart = selCaretPos;
-      selTargetEnd = selAnchorPos;
-      virtualSpaceLen = selCaretVspc;
-    }
-    else {
-      selTargetStart = selAnchorPos;
-      selTargetEnd = selCaretPos;
-      virtualSpaceLen = selAnchorVspc;
-    }
-
-    if (virtualSpaceLen > 0) {
-      char* pPadStr = LocalAlloc(LPTR, (virtualSpaceLen + length + 1) * sizeof(char));
-      if (pPadStr) {
-        SIZE_T size = LocalSize(pPadStr) - sizeof(char);
-        FillMemory(pPadStr, virtualSpaceLen, ' ');
-        pPadStr[virtualSpaceLen] = '\0';
-        StringCchCatNA(pPadStr, size, pTextLine, lnLen);
-        SciCall_SetTargetRange(selTargetStart, selTargetEnd);
-        SciCall_ReplaceTarget(lstrlenA(pPadStr), pPadStr);
-        LocalFree(pPadStr);
-      }
-      else {
-        SciCall_SetTargetRange(selTargetStart, selTargetEnd);
-        SciCall_ReplaceTarget(lnLen, pTextLine);
-      }
-    }
-    else // no virtual space to pad
-    {
-      SciCall_SetTargetRange(selTargetStart, selTargetEnd);
-      SciCall_ReplaceTarget(lnLen, pTextLine);
-    }
-
-    //SciCall_SetSelectionNAnchor(s, selTargetStart);
-    //SciCall_SetSelectionNCaret(s, selTargetStart);
-    //if (virtualSpaceLen > 0) {
-    //  SciCall_SetSelectionNCaretVirtualSpace(s, virtualSpaceLen);
-    //  SciCall_SetSelectionNAnchorVirtualSpace(s, virtualSpaceLen);
-    //}
-
-    if (*ln != '\0') {
-      pTextLine = ln; // next clip line
-    }
-    //else: rest of rect single selections are filled with last line
-  
-  } // for()
-
-  _LEAVE_TARGET_TRANSACTION_;
-  _OBSERVE_NOTIFY_CHANGE_;
-}
-
-
-//=============================================================================
-//
-//  EditPasteClipboard()
-//
-bool EditPasteClipboard(HWND hwnd, bool bSwapClipBoard, bool bSkipUnicodeCheck)
+bool EditSwapClipboard(HWND hwnd, bool bSkipUnicodeCheck)
 {
   int lineCount = 0;
   int lenLastLine = 0;
-
-  char* pClip = EditGetClipboardText(hwnd, !bSkipUnicodeCheck, &lineCount, &lenLastLine);
+  char* const pClip = EditGetClipboardText(hwnd, !bSkipUnicodeCheck, &lineCount, &lenLastLine);
   if (!pClip) {
     return false; // recoding canceled
   }
-  const DocPos clipLen = lstrlenA(pClip);
+  DocPos const clipLen = lstrlenA(pClip);
 
-  const DocPos iCurPos = SciCall_GetCurrentPos();
-  const DocPos iAnchorPos = SciCall_GetAnchor();
+  DocPos const iCurPos = SciCall_GetCurrentPos();
+  DocPos const iAnchorPos = SciCall_GetAnchor();
+  bool const bIsRectSel = SciCall_IsSelectionRectangle();
 
-  if (SciCall_IsSelectionEmpty() || (lineCount <= 1)) 
-  {
-    _IGNORE_NOTIFY_CHANGE_;
-
-    if (SciCall_IsSelectionEmpty()) // SC_SEL_THIN
-    {
-      SciCall_Paste();
-      if (bSwapClipBoard) { 
-        EditClearClipboard(hwnd);
-        EditSelectEx(hwnd, iAnchorPos, SciCall_GetCurrentPos(), -1, -1);
-      }
-      //else {
-      //  EditSelectEx(hwnd, SciCall_GetCurrentPos(), SciCall_GetCurrentPos(), -1, -1);
-      //}
-    }
-    else {
-      char* pszText = LocalAlloc(LPTR, SciCall_GetSelText(NULL));
-      SciCall_GetSelText(pszText);
-      if (clipLen == 0) { SciCall_Clear(); } else { SciCall_Paste(); }
-      if (bSwapClipBoard) {
-        EditSetClipboardText(hwnd, pszText);
-        if (iCurPos < iAnchorPos)
-          EditSelectEx(hwnd, SciCall_GetCurrentPos(), iCurPos, -1, -1);
-        else
-          EditSelectEx(hwnd, iAnchorPos, SciCall_GetCurrentPos(), -1, -1);
-      }
-      else {
-        if (iCurPos < iAnchorPos)
-          EditSelectEx(hwnd, iCurPos, iCurPos, -1, -1);
-      }
-      LocalFree(pszText);
-    }
-    _OBSERVE_NOTIFY_CHANGE_;
+  char* pszText = NULL;
+  SIZE_T const size = SciCall_GetSelText(NULL);
+  if (size > 0) {
+    pszText = LocalAlloc(LPTR, size);
+    SciCall_GetSelText(pszText);
+    SciCall_Paste();  //~SciCall_ReplaceSel(pClip);
+    EditSetClipboardText(hwnd, pszText);
   }
   else {
-    if (SciCall_IsSelectionRectangle()) 
-    {
-      if (bSwapClipBoard) { SciCall_Copy(); }
-      EditPaste2RectSel(hwnd, pClip);
-      //TODO: restore selection in case of swap clipboard 
-    }
-    else // Selection: SC_SEL_STREAM, SC_SEL_LINES
-    {
-      _IGNORE_NOTIFY_CHANGE_;
-      if (bSwapClipBoard) {
-        SciCall_Copy();
-        SciCall_ReplaceSel(pClip);
-        if (iCurPos < iAnchorPos)
-          EditSelectEx(hwnd, iCurPos + clipLen, iCurPos, -1, -1);
-        else
-          EditSelectEx(hwnd, iAnchorPos, iAnchorPos + clipLen, -1, -1);
-      }
-      else {
-        SciCall_ReplaceSel(pClip);
-        if (iCurPos < iAnchorPos)
-          EditSelectEx(hwnd, iCurPos, iCurPos, -1, -1);
-      }
-      _OBSERVE_NOTIFY_CHANGE_;
-    }
+    SciCall_Paste();  //~SciCall_ReplaceSel(pClip);
+    SciCall_Clear();
   }
+  if (pszText) { LocalFree(pszText); }
+
+  if (!bIsRectSel) {
+    //TODO: check for Rectangular Clipboard and skip selection restore
+    if (iCurPos < iAnchorPos)
+      EditSelectEx(hwnd, iCurPos + clipLen, iCurPos, -1, -1);
+    else
+      EditSelectEx(hwnd, iAnchorPos, iAnchorPos + clipLen, -1, -1);
+  }
+  else {
+    //TODO: restore selection in case of swap clipboard 
+  }
+
   LocalFree(pClip);
   return true;
 }
@@ -2697,23 +2569,8 @@ void EditIndentBlock(HWND hwnd, int cmd, bool bFormatIndentation)
 
   if (SciCall_IsSelectionRectangle()) 
   {
-    //if (cmd == SCI_TAB) {
-    //  if (g_bTabsAsSpaces) {
-    //    int size = (bFormatIndentation ? g_iIndentWidth : g_iTabWidth);
-    //    char* pPadStr = LocalAlloc(LPTR, size + 1);
-    //    FillMemory(pPadStr, size, ' ');
-    //    EditPaste2RectSel(hwnd, pPadStr);
-    //    LocalFree(pPadStr);
-    //  }
-    //  else {
-    //    EditPaste2RectSel(hwnd, "\t");
-    //  }
-    //  return;
-    //}
-    // better idea:  EditPaste2RectSel(hwnd, pPadStr, pText); pText==NULL => copy single sel
-
-    //TODO: workaround for rectangular selection: make stream selection
-    EditSelectEx(hwnd, SciCall_GetAnchor(), SciCall_GetCurrentPos(), -1, -1);
+    SendMessage(hwnd, cmd, 0, 0);
+    return;
   }
 
   const DocPos iCurPos = SciCall_GetCurrentPos();
@@ -3242,7 +3099,7 @@ void EditPadWithSpaces(HWND hwnd, bool bSkipEmpty, bool bNoUndoGroup)
 {
   if (SciCall_IsSelectionEmpty() || Sci_IsThinRectangleSelected()) { return; }
 
-  const int token = (!bNoUndoGroup ? BeginUndoAction() : -1);
+  int const token = (!bNoUndoGroup ? BeginUndoAction() : -1);
 
   if (SciCall_IsSelectionRectangle())
   {
@@ -5613,7 +5470,7 @@ INT_PTR CALLBACK EditFindReplaceDlgProcW(HWND hwnd,UINT umsg,WPARAM wParam,LPARA
         case IDC_REPLACE:
           {
             bReplaceInitialized = true;
-            int token = BeginUndoAction();
+            int const token = BeginUndoAction();
             EditReplace(sg_pefrData->hwnd, sg_pefrData);
             EndUndoAction(token);
           }
@@ -6238,7 +6095,7 @@ bool EditReplaceAll(HWND hwnd, LPCEDITFINDREPLACE lpefr, bool bShowInfo)
 
   BeginWaitCursor(NULL);
 
-  int token = BeginUndoAction();
+  int const token = BeginUndoAction();
 
   iReplacedOccurrences = EditReplaceAllInRange(hwnd, lpefr, start, end, &enlargement);
 
@@ -6274,7 +6131,7 @@ bool EditReplaceAllInSelection(HWND hwnd, LPCEDITFINDREPLACE lpefr, bool bShowIn
   const DocPos anchorPos = SciCall_GetAnchor();
   DocPos enlargement = 0;
 
-  int token = BeginUndoAction();
+  int const token = BeginUndoAction();
 
   bool const bWaitCursor = ((end - start) > (512 * 512)) ? true : false;
   if (bWaitCursor) { BeginWaitCursor(NULL); }
diff --git a/src/Edit.h b/src/Edit.h
index 9faedd35e..b4b4a014a 100644
--- a/src/Edit.h
+++ b/src/Edit.h
@@ -30,8 +30,7 @@ bool  EditIsRecodingNeeded(WCHAR*,int);
 char* EditGetClipboardText(HWND,bool,int*,int*);
 bool  EditSetClipboardText(HWND, const char*);
 bool  EditClearClipboard(HWND);
-void  EditPaste2RectSel(HWND,char*);
-bool  EditPasteClipboard(HWND,bool,bool);
+bool  EditSwapClipboard(HWND,bool);
 bool  EditCopyAppend(HWND,bool);
 int   EditDetectEOLMode(HWND,char*,DWORD);
 bool  EditLoadFile(HWND,LPCWSTR,bool,bool,int*,int*,bool*,bool*,bool*);
diff --git a/src/Notepad3.c b/src/Notepad3.c
index 17f6c7b46..dbceb5a79 100644
--- a/src/Notepad3.c
+++ b/src/Notepad3.c
@@ -1063,7 +1063,7 @@ HWND InitInstance(HINSTANCE hInstance,LPSTR pszCmdLine,int nCmdShow)
       bool bAutoIndent2 = bAutoIndent;
       bAutoIndent = 0;
       EditJumpTo(g_hwndEdit, -1, 0);
-      int token = BeginUndoAction();
+      int const token = BeginUndoAction();
       if (SendMessage(g_hwndEdit, SCI_GETLENGTH, 0, 0) > 0) {
         SendMessage(g_hwndEdit, SCI_NEWLINE, 0, 0);
       }
@@ -1239,6 +1239,12 @@ LRESULT CALLBACK MainWndProc(HWND hwnd,UINT umsg,WPARAM wParam,LPARAM lParam)
       }
       return DefWindowProc(hwnd, umsg, wParam, lParam);
 
+    case WM_KILLFOCUS:
+      if (bAltKeyIsDown) {
+        bAltKeyIsDown = false;
+        SciCall_SetVirtualSpaceOptions(bDenyVirtualSpaceAccess ? SCVS_NONE : SCVS_RECTANGULARSELECTION);
+      }
+      return DefWindowProc(hwnd, umsg, wParam, lParam);
 
     case WM_CREATE:
       return MsgCreate(hwnd,wParam,lParam);
@@ -1417,17 +1423,21 @@ static void __fastcall _InitializeSciEditCtrl(HWND hwndEditCtrl)
   Encoding_Current(g_iDefaultNewFileEncoding);
 
   // general setup
+  //int const evtMask = SC_MODEVENTMASKALL;
+  int const evtMask1 = SC_MOD_CONTAINER | SC_PERFORMED_USER | SC_PERFORMED_UNDO | SC_PERFORMED_REDO;
+  int const evtMask2 = SC_MOD_INSERTTEXT | SC_MOD_DELETETEXT | SC_MOD_BEFOREINSERT | SC_MOD_BEFOREDELETE | SC_STARTACTION;
+  SendMessage(hwndEditCtrl, SCI_SETMODEVENTMASK, (WPARAM)(evtMask1 | evtMask2), 0);
+
   SendMessage(hwndEditCtrl, SCI_SETCODEPAGE, (WPARAM)SC_CP_UTF8, 0); // fixed internal UTF-8 
   SendMessage(hwndEditCtrl, SCI_SETEOLMODE, SC_EOL_CRLF, 0);
   SendMessage(hwndEditCtrl, SCI_SETPASTECONVERTENDINGS, true, 0);
-  SendMessage(hwndEditCtrl, SCI_SETMODEVENTMASK,/*SC_MODEVENTMASKALL*/SC_MOD_INSERTTEXT | SC_MOD_DELETETEXT | SC_MOD_CONTAINER, 0);
   SendMessage(hwndEditCtrl, SCI_USEPOPUP, false, 0);
   SendMessage(hwndEditCtrl, SCI_SETSCROLLWIDTH, 1, 0);
   SendMessage(hwndEditCtrl, SCI_SETSCROLLWIDTHTRACKING, true, 0);
   SendMessage(hwndEditCtrl, SCI_SETENDATLASTLINE, true, 0);
   SendMessage(hwndEditCtrl, SCI_SETMOUSESELECTIONRECTANGULARSWITCH, true, 0);
   SendMessage(hwndEditCtrl, SCI_SETMULTIPLESELECTION, false, 0);
-  SendMessage(hwndEditCtrl, SCI_SETADDITIONALSELECTIONTYPING, false, 0);
+  SendMessage(hwndEditCtrl, SCI_SETADDITIONALSELECTIONTYPING, true, 0);
   SendMessage(hwndEditCtrl, SCI_SETADDITIONALCARETSBLINK, true, 0);
   SendMessage(hwndEditCtrl, SCI_SETADDITIONALCARETSVISIBLE, true, 0);
   SendMessage(hwndEditCtrl, SCI_SETVIRTUALSPACEOPTIONS, SCVS_NONE, 0);
@@ -2767,6 +2777,8 @@ LRESULT MsgSysCommand(HWND hwnd, UINT umsg, WPARAM wParam, LPARAM lParam)
 //
 LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 {
+  UNUSED(lParam);
+
   switch(LOWORD(wParam))
   {
     case SCEN_CHANGE:
@@ -3139,7 +3151,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
         if (g_flagPasteBoard)
           bLastCopyFromMe = true;
 
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         if (!SciCall_IsSelectionEmpty())
         {
           SciCall_Cut();
@@ -3186,13 +3198,14 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
       {
         if (g_flagPasteBoard)
           bLastCopyFromMe = true;
-        int token = BeginUndoAction();
-        EditPasteClipboard(g_hwndEdit, false, bSkipUnicodeDetection);
+        int const token = BeginUndoAction();
+        _IGNORE_NOTIFY_CHANGE_;
+        SciCall_Paste();
+        _OBSERVE_NOTIFY_CHANGE_;
         EndUndoAction(token);
-        // Updates done by EditPasteClipboard():
-        //~UpdateToolbar();
-        //~UpdateStatusbar(false);
-        //~UpdateLineNumberWidth();
+        UpdateToolbar();
+        UpdateStatusbar(false);
+        UpdateLineNumberWidth();
       }
       break;
 
@@ -3200,11 +3213,14 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
       {
         if (g_flagPasteBoard)
           bLastCopyFromMe = true;
-        int token = BeginUndoAction();
-        EditPasteClipboard(g_hwndEdit, true, bSkipUnicodeDetection);
+        int const token = BeginUndoAction();
+        _IGNORE_NOTIFY_CHANGE_;
+        EditSwapClipboard(g_hwndEdit, bSkipUnicodeDetection);
+        _OBSERVE_NOTIFY_CHANGE_;
         EndUndoAction(token);
         UpdateToolbar();
         UpdateStatusbar(false);
+        UpdateLineNumberWidth();
       }
       break;
 
@@ -3216,6 +3232,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case IDM_EDIT_SELECTALL:
         SendMessage(g_hwndEdit,SCI_SELECTALL,0,0);
+        UpdateToolbar();
         UpdateStatusbar(false);
       break;
 
@@ -3274,7 +3291,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case IDM_EDIT_MOVELINEUP:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditMoveUp(g_hwndEdit);
         EndUndoAction(token);
       }
@@ -3283,7 +3300,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case IDM_EDIT_MOVELINEDOWN:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditMoveDown(g_hwndEdit);
         EndUndoAction(token);
       }
@@ -3299,7 +3316,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
       {
         if (g_flagPasteBoard)
           bLastCopyFromMe = true;
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit,SCI_LINECUT,0,0);
         UpdateToolbar();
         EndUndoAction(token);
@@ -3309,7 +3326,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case IDM_EDIT_DELETELINE:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit, SCI_LINEDELETE, 0, 0);
         EndUndoAction(token);
       }
@@ -3318,7 +3335,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case IDM_EDIT_DELETELINELEFT:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit, SCI_DELLINELEFT, 0, 0);
         EndUndoAction(token);
       }
@@ -3327,7 +3344,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case IDM_EDIT_DELETELINERIGHT:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit, SCI_DELLINERIGHT, 0, 0);
         EndUndoAction(token);
       }
@@ -3336,7 +3353,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case IDM_EDIT_INDENT:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditIndentBlock(g_hwndEdit, SCI_TAB, true);
         EndUndoAction(token);
       }
@@ -3344,7 +3361,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case IDM_EDIT_UNINDENT:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditIndentBlock(g_hwndEdit, SCI_BACKTAB, true);
         EndUndoAction(token);
       }
@@ -3352,7 +3369,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_TAB:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditIndentBlock(g_hwndEdit, SCI_TAB, false);
         EndUndoAction(token);
       }
@@ -3360,7 +3377,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_BACKTAB:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditIndentBlock(g_hwndEdit, SCI_BACKTAB, false);
         EndUndoAction(token);
       }
@@ -3368,7 +3385,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_CTRLTAB:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit, SCI_SETUSETABS, true, 0);
         SendMessage(g_hwndEdit, SCI_SETTABINDENTS, false, 0);
         EditIndentBlock(g_hwndEdit, SCI_TAB, false);
@@ -3380,7 +3397,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_DELETEBACK:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit, SCI_DELETEBACK, 0, 0);
         EndUndoAction(token);
       }
@@ -3394,7 +3411,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_ENCLOSESELECTION:
       if (EditEncloseSelectionDlg(hwnd,wchPrefixSelection,wchAppendSelection)) {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditEncloseSelection(g_hwndEdit,wchPrefixSelection,wchAppendSelection);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3405,7 +3422,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_SELECTIONDUPLICATE:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit,SCI_SELECTIONDUPLICATE,0,0);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3425,7 +3442,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_STRIP1STCHAR:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditStripFirstCharacter(g_hwndEdit);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3436,7 +3453,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_STRIPLASTCHAR:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditStripLastCharacter(g_hwndEdit, false, false);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3447,7 +3464,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_TRIMLINES:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditStripLastCharacter(g_hwndEdit, false, true);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3458,7 +3475,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_COMPRESSWS:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditCompressSpaces(g_hwndEdit);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3469,7 +3486,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_MERGEBLANKLINES:
     {
       BeginWaitCursor(NULL);
-      int token = BeginUndoAction();
+      int const token = BeginUndoAction();
       EditRemoveBlankLines(g_hwndEdit, true, true);
       EndUndoAction(token);
       EndWaitCursor();
@@ -3479,7 +3496,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_MERGEEMPTYLINES:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditRemoveBlankLines(g_hwndEdit, true, false);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3490,7 +3507,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_REMOVEBLANKLINES:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditRemoveBlankLines(g_hwndEdit, false, true);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3501,7 +3518,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_REMOVEEMPTYLINES:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditRemoveBlankLines(g_hwndEdit, false, false);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3512,7 +3529,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_REMOVEDUPLICATELINES:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditRemoveDuplicateLines(g_hwndEdit, false);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3524,7 +3541,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
       {
         if (EditModifyLinesDlg(hwnd,wchPrefixLines,wchAppendLines)) {
           BeginWaitCursor(NULL);
-          int token = BeginUndoAction();
+          int const token = BeginUndoAction();
           EditModifyLines(g_hwndEdit,wchPrefixLines,wchAppendLines);
           EndUndoAction(token);
           EndWaitCursor();
@@ -3537,7 +3554,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
       {
         if (EditAlignDlg(hwnd,&iAlignMode)) {
           BeginWaitCursor(NULL);
-          int token = BeginUndoAction();
+          int const token = BeginUndoAction();
           EditAlignText(g_hwndEdit,iAlignMode);
           EndUndoAction(token);
           EndWaitCursor();
@@ -3550,7 +3567,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
       {
         if (EditSortDlg(hwnd,&iSortOptions)) {
           BeginWaitCursor(NULL);
-          int token = BeginUndoAction();
+          int const token = BeginUndoAction();
           EditSortLines(g_hwndEdit,iSortOptions);
           EndUndoAction(token);
           EndWaitCursor();
@@ -3570,7 +3587,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
         {
           iWrapCol = (DocPos)max(min(uWrpCol,(UINT)g_iLongLinesLimit),1);
           BeginWaitCursor(NULL);
-          int token = BeginUndoAction();
+          int const token = BeginUndoAction();
           EditWrapToColumn(g_hwndEdit,iWrapCol);
           EndUndoAction(token);
           EndWaitCursor();
@@ -3582,7 +3599,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_SPLITLINES:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditSplitLines(g_hwndEdit);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3593,7 +3610,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_JOINLINES:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditJoinLinesEx(g_hwndEdit, false, true);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3603,7 +3620,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_JOINLN_NOSP:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditJoinLinesEx(g_hwndEdit, false, false);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3613,7 +3630,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_JOINLINES_PARA:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditJoinLinesEx(g_hwndEdit, true, true);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3624,7 +3641,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_CONVERTUPPERCASE:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit,SCI_UPPERCASE,0,0);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3635,7 +3652,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_CONVERTLOWERCASE:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit,SCI_LOWERCASE,0,0);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3646,7 +3663,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_INVERTCASE:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditInvertCase(g_hwndEdit);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3657,7 +3674,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_TITLECASE:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditTitleCase(g_hwndEdit);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3668,7 +3685,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_SENTENCECASE:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditSentenceCase(g_hwndEdit);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3679,7 +3696,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_CONVERTTABS:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditTabsToSpaces(g_hwndEdit, g_iTabWidth, false);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3690,7 +3707,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_CONVERTSPACES:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditSpacesToTabs(g_hwndEdit, g_iTabWidth, false);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3701,7 +3718,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_CONVERTTABS2:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditTabsToSpaces(g_hwndEdit, g_iTabWidth, true);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3712,7 +3729,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_CONVERTSPACES2:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditSpacesToTabs(g_hwndEdit, g_iTabWidth, true);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3725,7 +3742,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
         WCHAR wszOpen[256] = { L'\0' };
         WCHAR wszClose[256] = { L'\0' };
         if (EditInsertTagDlg(hwnd, wszOpen, wszClose)) {
-          int token = BeginUndoAction();
+          int const token = BeginUndoAction();
           EditEncloseSelection(g_hwndEdit, wszOpen, wszClose);
           EndUndoAction(token);
         }
@@ -3742,7 +3759,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
           char *p = StrChrA(msz, ',');
           if (p)
             *p = 0;
-          int token = BeginUndoAction();
+          int const token = BeginUndoAction();
           SendMessage(g_hwndEdit,SCI_REPLACESEL,0,(LPARAM)msz);
           EndUndoAction(token);
         }
@@ -3788,7 +3805,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
         }
 
         WideCharToMultiByteStrg(Encoding_SciCP,tchDateTime,mszBuf);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit,SCI_REPLACESEL,0,(LPARAM)mszBuf);
         EndUndoAction(token);
       }
@@ -3819,7 +3836,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
         }
 
         WideCharToMultiByteStrg(Encoding_SciCP,pszInsert,mszBuf);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit,SCI_REPLACESEL,0,(LPARAM)mszBuf);
         EndUndoAction(token);
     }
@@ -3836,7 +3853,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
             wszGuid[wcslen(wszGuid) - 1] = L'\0'; // trim last brace char 
             char mszGuid[40 * 4]; // UTF-8 max of 4 bytes per char
             if (WideCharToMultiByteStrg(Encoding_SciCP,pwszGuid,mszGuid)) {
-              int token = BeginUndoAction();
+              int const token = BeginUndoAction();
               SendMessage(g_hwndEdit,SCI_REPLACESEL,0,(LPARAM)mszGuid);
               EndUndoAction(token);
             }
@@ -3849,7 +3866,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_LINECOMMENT:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
 
         switch (SendMessage(g_hwndEdit, SCI_GETLEXER, 0, 0)) {
         default:
@@ -3916,7 +3933,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_STREAMCOMMENT:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
 
         switch (SendMessage(g_hwndEdit, SCI_GETLEXER, 0, 0)) {
         default:
@@ -3977,7 +3994,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_URLENCODE:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditURLEncode(g_hwndEdit);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3988,7 +4005,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_URLDECODE:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditURLDecode(g_hwndEdit);
         EndUndoAction(token);
         EndWaitCursor();
@@ -3999,7 +4016,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_ESCAPECCHARS:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditEscapeCChars(g_hwndEdit);
         EndUndoAction(token);
         EndWaitCursor();
@@ -4010,7 +4027,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_UNESCAPECCHARS:
       {
         BeginWaitCursor(NULL);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditUnescapeCChars(g_hwndEdit);
         EndUndoAction(token);
         EndWaitCursor();
@@ -4020,7 +4037,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case IDM_EDIT_CHAR2HEX:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditChar2Hex(g_hwndEdit);
         EndUndoAction(token);
       }
@@ -4039,7 +4056,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case IDM_EDIT_SELTOMATCHINGBRACE:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditSelectToMatchingBrace(g_hwndEdit);
         EndUndoAction(token);
       }
@@ -4878,7 +4895,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_CTRLENTER:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         const DocPos iPos = SciCall_GetCurrentPos();
         const DocLn iLine = SciCall_LineFromPosition(iPos);
         if (iLine <= 0) {
@@ -4906,7 +4923,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
     case IDM_EDIT_CLEAR:
     case CMD_DEL:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SciCall_Clear();
         EndUndoAction(token);
       }
@@ -4932,7 +4949,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
         const DocPos iIndentPos = SciCall_GetLineIndentPosition(iLine);
 
         if (iPos != iAnchor) {
-          int token = BeginUndoAction();
+          int const token = BeginUndoAction();
           SciCall_SetSel(iPos, iPos);
           EndUndoAction(token);
         }
@@ -4957,7 +4974,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
         const DocPos iEndPos = SciCall_GetLineEndPosition(iLine);
 
         if (iPos != iAnchor) {
-          int token = BeginUndoAction();
+          int const token = BeginUndoAction();
           SciCall_SetSel(iPos, iPos);
           EndUndoAction(token);
         }
@@ -5203,7 +5220,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_STRINGIFY:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditEncloseSelection(g_hwndEdit, L"'", L"'");
         EndUndoAction(token);
       }
@@ -5212,7 +5229,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_STRINGIFY2:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditEncloseSelection(g_hwndEdit, L"\"", L"\"");
         EndUndoAction(token);
       }
@@ -5221,7 +5238,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_EMBRACE:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditEncloseSelection(g_hwndEdit, L"(", L")");
         EndUndoAction(token);
       }
@@ -5230,7 +5247,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_EMBRACE2:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditEncloseSelection(g_hwndEdit, L"[", L"]");
         EndUndoAction(token);
       }
@@ -5239,7 +5256,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_EMBRACE3:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditEncloseSelection(g_hwndEdit, L"{", L"}");
         EndUndoAction(token);
       }
@@ -5248,7 +5265,7 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
     case CMD_EMBRACE4:
       {
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         EditEncloseSelection(g_hwndEdit, L"`", L"`");
         EndUndoAction(token);
       }
@@ -5558,10 +5575,6 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
       break;
 
   }
-
-  UNUSED(wParam);
-  UNUSED(lParam);
-
   return(0);
 }
 
@@ -5663,6 +5676,7 @@ void OpenHotSpotURL(DocPos position, bool bForceBrowser)
 //
 //  MsgNotify() - Handles WM_NOTIFY
 //
+//  !!! Set correct SCI_SETMODEVENTMASK in _InitializeSciEditCtrl()
 //
 LRESULT MsgNotify(HWND hwnd,WPARAM wParam,LPARAM lParam)
 {
@@ -5674,6 +5688,7 @@ LRESULT MsgNotify(HWND hwnd,WPARAM wParam,LPARAM lParam)
     // --- check only mandatory events (must be fast !!!) ---
     if (pnmh->idFrom == IDC_EDIT) {
       if (pnmh->code == SCN_MODIFIED) {
+        bool bModified = true;
         // check for ADDUNDOACTION step
         if (scn->modificationType & SC_MOD_CONTAINER)
         {
@@ -5684,7 +5699,15 @@ LRESULT MsgNotify(HWND hwnd,WPARAM wParam,LPARAM lParam)
             RestoreAction(scn->token, REDO);
           }
         }
-        _SetDocumentModified(true);
+        else if ((scn->modificationType & SC_MOD_BEFOREINSERT) ||
+                 (scn->modificationType & SC_MOD_BEFOREDELETE)) {
+          if (!(scn->modificationType & SC_STARTACTION) && !SciCall_IsSelectionEmpty()) {
+            int const token = BeginUndoAction();
+            if (token >= 0) { EndUndoAction(token); }
+          }
+          bModified = false;  // not yet
+        }
+        if (bModified) { _SetDocumentModified(true); }
       }
       else if (pnmh->code == SCN_SAVEPOINTREACHED) {
         _SetDocumentModified(false);
@@ -5782,7 +5805,7 @@ LRESULT MsgNotify(HWND hwnd,WPARAM wParam,LPARAM lParam)
 
         case SCN_MODIFIED:
           {
-            // check for ADDUNDOACTION step
+            bool bModified = true;
             if (scn->modificationType & SC_MOD_CONTAINER) {
               if (scn->modificationType & SC_PERFORMED_UNDO) {
                 RestoreAction(scn->token, UNDO);
@@ -5791,6 +5814,14 @@ LRESULT MsgNotify(HWND hwnd,WPARAM wParam,LPARAM lParam)
                 RestoreAction(scn->token, REDO);
               }
             }
+            else if ((scn->modificationType & SC_MOD_BEFOREINSERT) ||
+                     (scn->modificationType & SC_MOD_BEFOREDELETE)) {
+              if (!(scn->modificationType & SC_STARTACTION) && !SciCall_IsSelectionEmpty()) {
+                int const token = BeginUndoAction();
+                if (token >= 0) { EndUndoAction(token); }
+              }
+              bModified = false; // not yet
+            }
             else if (scn->modificationType & SC_MOD_CHANGESTYLE) {
               const DocPos iStartPos = (DocPos)scn->position;
               const DocPos iEndPos = (DocPos)(scn->position + scn->length);
@@ -5806,7 +5837,7 @@ LRESULT MsgNotify(HWND hwnd,WPARAM wParam,LPARAM lParam)
               UpdateLineNumberWidth();
             }
 
-            _SetDocumentModified(true);
+            if (bModified) { _SetDocumentModified(true); }
 
             UpdateToolbar();
             UpdateStatusbar(false);
@@ -5861,7 +5892,7 @@ LRESULT MsgNotify(HWND hwnd,WPARAM wParam,LPARAM lParam)
                         *pPos = '\0';
                     }
                     if (*pLineBuf) {
-                      int token = BeginUndoAction();
+                      int const token = BeginUndoAction();
                       SciCall_AddText(lstrlenA(pLineBuf), pLineBuf);
                       EndUndoAction(token);
                     }
@@ -5915,7 +5946,7 @@ LRESULT MsgNotify(HWND hwnd,WPARAM wParam,LPARAM lParam)
                       StringCchCompareINA(g_pTempLineBufferMain, COUNTOF(g_pTempLineBufferMain), "</link>", -1) &&
                       StringCchCompareINA(g_pTempLineBufferMain, COUNTOF(g_pTempLineBufferMain), "</meta>", -1))
                     {
-                      int token = BeginUndoAction();
+                      int const token = BeginUndoAction();
                       SciCall_ReplaceSel(g_pTempLineBufferMain);
                       SciCall_SetSel(iCurPos, iCurPos);
                       EndUndoAction(token);
@@ -8026,7 +8057,7 @@ int BeginUndoAction()
     break;
   }
 
-  int token = UndoRedoActionMap(-1, &sel);
+  int const token = UndoRedoActionMap(-1, &sel);
  
   if (token >= 0) {
     SciCall_BeginUndoAction();
@@ -8436,7 +8467,7 @@ bool FileLoad(bool bDontSave, bool bNew, bool bReload, bool bSkipUnicodeDetect,
       SendMessage(g_hwndEdit,SCI_GETTEXT,5,(LPARAM)tchLog);
       if (StringCchCompareXA(tchLog,".LOG") == 0) {
         EditJumpTo(g_hwndEdit,-1,0);
-        int token = BeginUndoAction();
+        int const token = BeginUndoAction();
         SendMessage(g_hwndEdit,SCI_NEWLINE,0,0);
         SendMessage(g_hwndMain,WM_COMMAND,MAKELONG(IDM_EDIT_INSERT_SHORTDATE,1),0);
         EditJumpTo(g_hwndEdit,-1,0);
@@ -9486,7 +9517,7 @@ void CALLBACK PasteBoardTimer(HWND hwnd,UINT uMsg,UINT_PTR idEvent,DWORD dwTime)
       bool bAutoIndent2 = bAutoIndent;
       bAutoIndent = 0;
       EditJumpTo(g_hwndEdit,-1,0);
-      int token = BeginUndoAction();
+      int const token = BeginUndoAction();
       if (SendMessage(g_hwndEdit, SCI_GETLENGTH, 0, 0) > 0) {
         SendMessage(g_hwndEdit, SCI_NEWLINE, 0, 0);
       }
diff --git a/src/SciCall.h b/src/SciCall.h
index 61d62d909..64b87ce6e 100644
--- a/src/SciCall.h
+++ b/src/SciCall.h
@@ -138,11 +138,7 @@ DeclareSciCallR0(GetReadOnly, GETREADONLY, bool)
 DeclareSciCallV1(SetReadOnly, SETREADONLY, bool, flag)
 DeclareSciCallR0(CanUndo, CANUNDO, bool)
 DeclareSciCallR0(CanRedo, CANREDO, bool)
-
 DeclareSciCallR0(IsDocModified, GETMODIFY, bool)
-DeclareSciCallR0(IsSelectionEmpty, GETSELECTIONEMPTY, bool)
-DeclareSciCallR0(IsSelectionRectangle, SELECTIONISRECTANGLE, bool)
-
 DeclareSciCallR0(CanPaste, CANPASTE, bool)
 
 DeclareSciCallR0(GetCurrentPos, GETCURRENTPOS, DocPos)
@@ -367,11 +363,12 @@ DeclareSciCallV1(SetTechnology, SETTECHNOLOGY, int, technology)
 //
 //  Utilities
 //
+DeclareSciCallR0(IsSelectionEmpty, GETSELECTIONEMPTY, bool)
+DeclareSciCallR0(IsSelectionRectangle, SELECTIONISRECTANGLE, bool)
 #define Sci_IsStreamSelected() (SciCall_GetSelectionMode() == SC_SEL_STREAM)
 #define Sci_IsFullLineSelected() (SciCall_GetSelectionMode() == SC_SEL_LINES)
 #define Sci_IsThinRectangleSelected() (SciCall_GetSelectionMode() == SC_SEL_THIN)
-#define Sci_IsSingleLineSelection() \
-(SciCall_LineFromPosition(SciCall_GetCurrentPos()) == SciCall_LineFromPosition(SciCall_GetAnchor()))
+#define Sci_IsSingleLineSelection() (SciCall_LineFromPosition(SciCall_GetCurrentPos()) == SciCall_LineFromPosition(SciCall_GetAnchor()))
 
 #define Sci_GetEOLLen() ((SciCall_GetEOLMode() == SC_EOL_CRLF) ? 2 : 1)