diff --git a/src/Edit.c b/src/Edit.c
index 6440db3e7..794828ca9 100644
--- a/src/Edit.c
+++ b/src/Edit.c
@@ -161,7 +161,7 @@ HWND EditCreate(HWND hwndParent)
   SendMessage(hwnd,SCI_SETADDITIONALCARETSBLINK,FALSE,0);
   SendMessage(hwnd,SCI_SETADDITIONALCARETSVISIBLE,FALSE,0);
   SendMessage(hwnd,SCI_SETMOUSEWHEELCAPTURES,FALSE,0);
-  SendMessage(hwnd, SCI_SETVIRTUALSPACEOPTIONS, (bDenyVirtualSpaceAccess ? SCVS_NONE : SCVS_NP3_SPACE_OPT), 0);
+  SendMessage(hwnd, SCI_SETVIRTUALSPACEOPTIONS, (bDenyVirtualSpaceAccess ? SCVS_NONE : SCVS_RECTANGULARSELECTION), 0);
 
   SendMessage(hwnd,SCI_ASSIGNCMDKEY,(SCK_NEXT + (SCMOD_CTRL << 16)),SCI_PARADOWN);
   SendMessage(hwnd,SCI_ASSIGNCMDKEY,(SCK_PRIOR + (SCMOD_CTRL << 16)),SCI_PARAUP);
@@ -4494,14 +4494,18 @@ INT_PTR CALLBACK EditFindReplaceDlgProcW(HWND hwnd,UINT umsg,WPARAM wParam,LPARA
         case IDC_FINDTEXT:
         case IDC_REPLACETEXT:
           {
-            BOOL bEnable = (GetWindowTextLengthW(GetDlgItem(hwnd,IDC_FINDTEXT)) ||
-                            CB_ERR != SendDlgItemMessage(hwnd,IDC_FINDTEXT,CB_GETCURSEL,0,0));
+            BOOL bEnableF = (GetWindowTextLengthW(GetDlgItem(hwnd,IDC_FINDTEXT)) ||
+              CB_ERR != SendDlgItemMessage(hwnd,IDC_FINDTEXT,CB_GETCURSEL,0,0));
 
-            EnableWindow(GetDlgItem(hwnd,IDOK),bEnable);
-            EnableWindow(GetDlgItem(hwnd,IDC_FINDPREV),bEnable);
-            EnableWindow(GetDlgItem(hwnd,IDC_REPLACE),bEnable);
-            EnableWindow(GetDlgItem(hwnd,IDC_REPLACEALL),bEnable);
-            EnableWindow(GetDlgItem(hwnd,IDC_REPLACEINSEL),bEnable);
+            BOOL bEnableR = (GetWindowTextLengthW(GetDlgItem(hwnd, IDC_REPLACETEXT)) ||
+              CB_ERR != SendDlgItemMessage(hwnd, IDC_REPLACETEXT, CB_GETCURSEL, 0, 0));
+
+            EnableWindow(GetDlgItem(hwnd,IDOK),bEnableF);
+            EnableWindow(GetDlgItem(hwnd,IDC_FINDPREV),bEnableF);
+            EnableWindow(GetDlgItem(hwnd,IDC_REPLACE),bEnableF);
+            EnableWindow(GetDlgItem(hwnd,IDC_REPLACEALL),bEnableF);
+            EnableWindow(GetDlgItem(hwnd,IDC_REPLACEINSEL),bEnableF);
+            EnableWindow(GetDlgItem(hwnd,IDC_SWAPSTRG),bEnableF || bEnableR);
 
             if (HIWORD(wParam) == CBN_CLOSEUP) {
               LONG lSelEnd;
@@ -4557,13 +4561,15 @@ INT_PTR CALLBACK EditFindReplaceDlgProcW(HWND hwnd,UINT umsg,WPARAM wParam,LPARA
           cpLastFind = uCPEdit;
 
           if (!bSwitchedFindReplace &&
-              !GetDlgItemTextA2W(uCPEdit,hwnd,IDC_FINDTEXT,lpefr->szFind,COUNTOF(lpefr->szFind))) {
-
+              !GetDlgItemTextA2W(uCPEdit,hwnd,IDC_FINDTEXT,lpefr->szFind,COUNTOF(lpefr->szFind))) 
+          {
             EnableWindow(GetDlgItem(hwnd,IDOK),FALSE);
             EnableWindow(GetDlgItem(hwnd,IDC_FINDPREV),FALSE);
             EnableWindow(GetDlgItem(hwnd,IDC_REPLACE),FALSE);
             EnableWindow(GetDlgItem(hwnd,IDC_REPLACEALL),FALSE);
             EnableWindow(GetDlgItem(hwnd,IDC_REPLACEINSEL),FALSE);
+            if (!GetDlgItemTextA2W(uCPEdit, hwnd, IDC_REPLACETEXT, lpefr->szReplace, COUNTOF(lpefr->szReplace)))
+              EnableWindow(GetDlgItem(hwnd,IDC_SWAPSTRG),FALSE);
             return TRUE;
           }
 
@@ -4698,6 +4704,18 @@ INT_PTR CALLBACK EditFindReplaceDlgProcW(HWND hwnd,UINT umsg,WPARAM wParam,LPARA
           DestroyWindow(hwnd);
           break;
 
+        case IDC_SWAPSTRG:
+          {
+            WCHAR wszFind[1024] = { L'\0' };
+            WCHAR wszRepl[1024] = { L'\0' };
+            GetDlgItemTextW(hwnd, IDC_FINDTEXT, wszFind, COUNTOF(wszFind));
+            GetDlgItemTextW(hwnd, IDC_REPLACETEXT, wszRepl, COUNTOF(wszRepl));
+            SetDlgItemTextW(hwnd, IDC_FINDTEXT, wszRepl);
+            SetDlgItemTextW(hwnd, IDC_REPLACETEXT, wszFind);
+            PostMessage(hwnd, WM_COMMAND, MAKELONG(IDC_FINDTEXT, 1), 0);
+          }
+          break;
+
         case IDACC_FIND:
           PostMessage(GetParent(hwnd),WM_COMMAND,MAKELONG(IDM_EDIT_FIND,1),0);
           break;
@@ -4736,7 +4754,6 @@ INT_PTR CALLBACK EditFindReplaceDlgProcW(HWND hwnd,UINT umsg,WPARAM wParam,LPARA
           CheckDlgButton(hwnd,IDC_FINDTRANSFORMBS,BST_UNCHECKED);
           PostMessage(hwnd,WM_NEXTDLGCTL,(WPARAM)(GetDlgItem(hwnd,IDC_FINDTEXT)),1);
           break;
-
       }
 
       return TRUE;
@@ -5352,6 +5369,7 @@ void EditMarkAll(HWND hwnd, BOOL bMarkOccurrencesMatchCase, BOOL bMarkOccurrence
   // clear existing marker indicators
   SendMessage(hwnd, SCI_SETINDICATORCURRENT, INDIC_NP3_MARK_OCCURANCE, 0);
   SendMessage(hwnd, SCI_INDICATORCLEARRANGE, 0, iTextLen);
+  iMarkOccurrencesCount = -1;
 
   // if nothing selected or multiple lines are selected exit
   if ((iSelCount == 0) ||
@@ -5401,7 +5419,6 @@ void EditMarkAll(HWND hwnd, BOOL bMarkOccurrencesMatchCase, BOOL bMarkOccurrence
   LocalFree(pszText);
 
   UpdateStatusbar();
-  iMarkOccurrencesCount = 0;
 
   return;
 }
diff --git a/src/Helpers.h b/src/Helpers.h
index 441aae1f3..330f4697a 100644
--- a/src/Helpers.h
+++ b/src/Helpers.h
@@ -97,9 +97,6 @@ __inline BOOL IniSectionSetBool(LPWSTR lpCachedIniSection, LPCWSTR lpName, BOOL
 #define IsWinServer() IsWindowsServer()          // Indicates if the current OS is a Windows Server release.
                                                  //   Applications that need to distinguish between server and client versions of Windows should call this function.
 
-#define SCVS_NP3_SPACE_OPT (SCVS_RECTANGULARSELECTION | SCVS_NOWRAPLINESTART)
-
-
 enum BufferSizes {
   MICRO_BUFFER =   32,
   MINI_BUFFER  =   64,
diff --git a/src/Notepad3.c b/src/Notepad3.c
index 76fc41a01..548077e4c 100644
--- a/src/Notepad3.c
+++ b/src/Notepad3.c
@@ -1148,13 +1148,10 @@ LRESULT CALLBACK MainWndProc(HWND hwnd,UINT umsg,WPARAM wParam,LPARAM lParam)
 {
   if (!bDenyVirtualSpaceAccess)
   {
-    if (GetAsyncKeyState(VK_MENU) & SHRT_MIN) { // ALT-KEY DOWN
-      //SendMessage(hwndEdit,SCI_CLEARSELECTIONS,0,0);
-      SendMessage(hwndEdit, SCI_SETVIRTUALSPACEOPTIONS, (SCVS_NP3_SPACE_OPT | SCVS_USERACCESSIBLE), 0);
-    }
-    else {
-      SendMessage(hwndEdit, SCI_SETVIRTUALSPACEOPTIONS, SCVS_NP3_SPACE_OPT, 0);
-    }
+    if (GetAsyncKeyState(VK_MENU) & SHRT_MIN)  // ALT-KEY DOWN
+      SendMessage(hwndEdit, SCI_SETVIRTUALSPACEOPTIONS, (SCVS_RECTANGULARSELECTION | SCVS_USERACCESSIBLE), 0);
+    else
+      SendMessage(hwndEdit, SCI_SETVIRTUALSPACEOPTIONS, SCVS_RECTANGULARSELECTION, 0);
   }
 
   switch(umsg)
@@ -2968,10 +2965,7 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
       {
         if (flagPasteBoard)
           bLastCopyFromMe = TRUE;
-
-        int token = BeginSelUndoAction();
         SendMessage(hwndEdit, SCI_COPYALLOWLINE, 0, 0);
-        EndSelUndoAction(token);
         UpdateToolbar();
       }
       break;
@@ -2981,10 +2975,7 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
       {
         if (flagPasteBoard)
           bLastCopyFromMe = TRUE;
-
-        int token = BeginSelUndoAction();
         SendMessage(hwndEdit,SCI_COPYRANGE,0,SendMessage(hwndEdit,SCI_GETLENGTH,0,0));
-        EndSelUndoAction(token);
         UpdateToolbar();
       }
       break;
@@ -2994,10 +2985,7 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
       {
         if (flagPasteBoard)
           bLastCopyFromMe = TRUE;
-
-        int token = BeginSelUndoAction();
         EditCopyAppend(hwndEdit);
-        EndSelUndoAction(token);
         UpdateToolbar();
       }
       break;
@@ -3013,8 +3001,6 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
         if (!pClip)
           break; // recoding canceled
 
-        int token = BeginSelUndoAction();
-
         if (SendMessage(hwndEdit,SCI_GETSELECTIONEMPTY,0,0))
         {
           int iCurPos = (int)SendMessage(hwndEdit,SCI_GETCURRENTPOS,0,0);
@@ -3033,6 +3019,7 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
 
         }
         else {
+          int token = BeginSelUndoAction();
 
           int iCurrPos = (int)SendMessage(hwndEdit, SCI_GETCURRENTPOS, 0, 0);
           int iAnchor = (int)SendMessage(hwndEdit, SCI_GETANCHOR, 0, 0);
@@ -3051,8 +3038,9 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
             else
               SendMessage(hwndEdit, SCI_SETSEL, iCurrPos + lstrlenA(pClip), iCurrPos);
           }
+
+          EndSelUndoAction(token);
         }
-        EndSelUndoAction(token);
         LocalFree(pClip);
         UpdateToolbar();
         UpdateStatusbar();
@@ -3078,17 +3066,13 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
 
     case IDM_EDIT_SELECTALL:
       {
-        int token = BeginSelUndoAction();
         SendMessage(hwndEdit,SCI_SELECTALL,0,0);
-        EndSelUndoAction(token);
       }
       break;
 
 
     case IDM_EDIT_SELECTWORD:
       {
-        int token = BeginSelUndoAction();
-
         int iPos = (int)SendMessage(hwndEdit,SCI_GETCURRENTPOS,0,0);
 
         if (SendMessage(hwndEdit, SCI_GETSELECTIONEMPTY, 0, 0)) {
@@ -3129,14 +3113,12 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
           int iLineEnd   = (int)SendMessage(hwndEdit,SCI_GETLINEENDPOSITION,iLine,0);
           SendMessage(hwndEdit,SCI_SETSEL,iLineStart,iLineEnd);
         }
-        EndSelUndoAction(token);
       }
       break;
 
 
     case IDM_EDIT_SELECTLINE:
       {
-        int token = BeginSelUndoAction();
         int iSelStart  = (int)SendMessage(hwndEdit,SCI_GETSELECTIONSTART,0,0);
         int iSelEnd    = (int)SendMessage(hwndEdit,SCI_GETSELECTIONEND,0,0);
         int iLineStart = (int)SendMessage(hwndEdit,SCI_LINEFROMPOSITION,iSelStart,0);
@@ -3145,7 +3127,6 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
         iSelEnd   = (int)SendMessage(hwndEdit,SCI_POSITIONFROMLINE,iLineEnd+1,0);
         SendMessage(hwndEdit,SCI_SETSEL,iSelStart,iSelEnd);
         SendMessage(hwndEdit,SCI_CHOOSECARETX,0,0);
-        EndSelUndoAction(token);
       }
       break;
 
@@ -3169,7 +3150,6 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
       {
         if (flagPasteBoard)
           bLastCopyFromMe = TRUE;
-
         int token = BeginSelUndoAction();
         SendMessage(hwndEdit,SCI_LINECUT,0,0);
         UpdateToolbar();
@@ -3181,24 +3161,35 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
     case IDM_EDIT_COPYLINE:
       if (flagPasteBoard)
         bLastCopyFromMe = TRUE;
-
       SendMessage(hwndEdit,SCI_LINECOPY,0,0);
       UpdateToolbar();
       break;
 
 
     case IDM_EDIT_DELETELINE:
-      SendMessage(hwndEdit,SCI_LINEDELETE,0,0);
+      {
+        int token = BeginSelUndoAction();
+        SendMessage(hwndEdit, SCI_LINEDELETE, 0, 0);
+        EndSelUndoAction(token);
+      }
       break;
 
 
     case IDM_EDIT_DELETELINELEFT:
-      SendMessage(hwndEdit,SCI_DELLINELEFT,0,0);
+      {
+        int token = BeginSelUndoAction();
+        SendMessage(hwndEdit, SCI_DELLINELEFT, 0, 0);
+        EndSelUndoAction(token);
+      }
       break;
 
 
     case IDM_EDIT_DELETELINERIGHT:
-      SendMessage(hwndEdit,SCI_DELLINERIGHT,0,0);
+      {
+        int token = BeginSelUndoAction();
+        SendMessage(hwndEdit, SCI_DELLINERIGHT, 0, 0);
+        EndSelUndoAction(token);
+      }
       break;
 
 
@@ -4225,6 +4216,7 @@ LRESULT MsgCommand(HWND hwnd,WPARAM wParam,LPARAM lParam)
       // clear all marks
       SendMessage(hwndEdit, SCI_SETINDICATORCURRENT, INDIC_NP3_MARK_OCCURANCE, 0);
       SendMessage(hwndEdit, SCI_INDICATORCLEARRANGE, 0, (int)SendMessage(hwndEdit,SCI_GETLENGTH,0,0));
+      iMarkOccurrencesCount = -1;
       break;
 
     case IDM_VIEW_MARKOCCURRENCES_RED:
diff --git a/src/Notepad3.rc b/src/Notepad3.rc
index d0cb0633d..911332e04 100644
Binary files a/src/Notepad3.rc and b/src/Notepad3.rc differ
diff --git a/src/resource.h b/src/resource.h
index b8f6cc227..330101953 100644
--- a/src/resource.h
+++ b/src/resource.h
@@ -1,6 +1,6 @@
 //{{NO_DEPENDENCIES}}
-// Microsoft Visual C++ generated include file.
-// Used by Notepad3.rc
+// Von Microsoft Visual C++ generierte Includedatei.
+// Verwendet durch Notepad3.rc
 //
 #define IDR_RT_MANIFEST                 1
 #define IDR_MAINWND                     100
@@ -123,6 +123,7 @@
 #define IDC_SCI_VERSION                 155
 #define IDR_MAINWND2                    156
 #define IDC_REMOVE                      157
+#define IDC_SWAPSTRG                    158
 #define IDACC_FIND                      200
 #define IDACC_REPLACE                   201
 #define IDACC_SAVEPOS                   202
@@ -468,7 +469,7 @@
 #define _APS_NO_MFC                     1
 #define _APS_NEXT_RESOURCE_VALUE        600
 #define _APS_NEXT_COMMAND_VALUE         700
-#define _APS_NEXT_CONTROL_VALUE         800
+#define _APS_NEXT_CONTROL_VALUE         801
 #define _APS_NEXT_SYMED_VALUE           900
 #endif
 #endif