diff --git a/src/Edit.c b/src/Edit.c
index b8f39dcdd..f18ea5a55 100644
--- a/src/Edit.c
+++ b/src/Edit.c
@@ -73,6 +73,7 @@ extern bool bFindReplCopySelOrClip;
 
 static EDITFINDREPLACE efrSave;
 static bool bSwitchedFindReplace = false;
+static bool bHideNonMatchedLines = false;
 
 extern int xFindReplaceDlg;
 extern int yFindReplaceDlg;
@@ -4715,12 +4716,24 @@ static RegExResult_t __fastcall _FindHasMatch(HWND hwnd, LPCEDITFINDREPLACE lpef
   DocPos end   = iTextLength;
   const DocPos iPos  = _FindInTarget(hwnd, szFind, slen, (int)(lpefr->fuFlags), &start, &end, false, FRMOD_IGNORE);
 
+  static DocLn lastScrollToLn = -1;
+
   if (bFirstMatchOnly && !bReplaceInitialized) {
-    if (iPos >= 0) {
-      EditScrollTo(hwnd, SciCall_LineFromPosition(iPos), true);
-    }
-    else {
-      EditScrollTo(hwnd, SciCall_LineFromPosition(iStart), false);
+    if (!bHideNonMatchedLines) {
+      if (iPos >= 0) {
+        const DocLn scrollToLn = SciCall_LineFromPosition(iPos);
+        if (scrollToLn != lastScrollToLn) {
+          EditScrollTo(hwnd, scrollToLn, true);
+          lastScrollToLn = scrollToLn;
+        }
+      }
+      else {
+        const DocLn scrollToLn = SciCall_LineFromPosition(iStart);
+        if (scrollToLn != lastScrollToLn) {
+          EditScrollTo(hwnd, scrollToLn, false);
+          lastScrollToLn = scrollToLn;
+        }
+      }
     }
   }
   else // mark all matches
@@ -4765,7 +4778,6 @@ INT_PTR CALLBACK EditFindReplaceDlgProcW(HWND hwnd,UINT umsg,WPARAM wParam,LPARA
   static RegExResult_t regexMatch = INVALID;
 
   static bool bFlagsChanged = true;
-  static bool bHideNonMatchedLines = false;
 
   static COLORREF rgbRed = RGB(255, 170, 170);
   static COLORREF rgbGreen = RGB(170, 255, 170);
@@ -5163,10 +5175,14 @@ INT_PTR CALLBACK EditFindReplaceDlgProcW(HWND hwnd,UINT umsg,WPARAM wParam,LPARA
         EnableCmd(GetMenu(g_hwndMain), IDM_VIEW_HYPERLINKHOTSPOTS, bHyperlinkHotspot);
         bFlagsChanged = true;
         _SetTimerMarkAll(hwnd, 0);
-        if (bHideNonMatchedLines)
+        if (bHideNonMatchedLines) {
           EditScrollTo(g_hwndEdit, 0, false);
-        else
+          SendMessage(g_hwndEdit, SCI_SETREADONLY, true, 0);
+        }
+        else {
           EditScrollTo(g_hwndEdit, Sci_GetCurrentLine(), true);
+          SendMessage(g_hwndEdit, SCI_SETREADONLY, false, 0);
+        }
       }
       break;
 
@@ -6408,12 +6424,10 @@ void EditUpdateUrlHotspots(HWND hwnd, DocPos startPos, DocPos endPos, bool bActi
 //
 void EditHideNotMarkedLineRange(HWND hwnd, DocPos iStartPos, DocPos iEndPos, bool bHide)
 {
-  static bool bLastState = true;
-  //UNUSED(hwnd);
+  UNUSED(hwnd);
 
   if (!bHide) {
     //SendMessage(hwnd, SCI_FOLDALL, (WPARAM)SC_FOLDACTION_EXPAND, 0);
-    bLastState = bHide;
     return; 
   }
 
@@ -6442,6 +6456,7 @@ void EditHideNotMarkedLineRange(HWND hwnd, DocPos iStartPos, DocPos iEndPos, boo
 
 
   const int baseLevel = SC_FOLDLEVELBASE;
+  const int headerLevel = SC_FOLDLEVELBASE | SC_FOLDLEVELHEADERFLAG;
   const int hiddenLevel = (SC_FOLDLEVELBASE + 1) | SC_FOLDLEVELWHITEFLAG;
 
   bool bHdrFlag = false;
@@ -6456,7 +6471,7 @@ void EditHideNotMarkedLineRange(HWND hwnd, DocPos iStartPos, DocPos iEndPos, boo
     }
     if (bIsHidden) {
       if (!bHdrFlag) {
-        SendMessage(hwnd, SCI_SETFOLDLEVEL, (WPARAM)iLine, (LPARAM)(baseLevel | SC_FOLDLEVELHEADERFLAG));
+        SendMessage(hwnd, SCI_SETFOLDLEVEL, (WPARAM)iLine, (LPARAM)headerLevel);
         bHdrFlag = true;
       }
       else
diff --git a/src/Notepad3.c b/src/Notepad3.c
index 6c7c20f62..c64974359 100644
--- a/src/Notepad3.c
+++ b/src/Notepad3.c
@@ -2594,11 +2594,6 @@ LRESULT MsgCommand(HWND hwnd, WPARAM wParam, LPARAM lParam)
 
 
     case IDM_FILE_READONLY:
-      //bReadOnly = (bReadOnly) ? false : true;
-      //SendMessage(g_hwndEdit,SCI_SETREADONLY,bReadOnly,0);
-      //UpdateToolbar();
-      //UpdateStatusbar();
-
       if (StringCchLenW(g_wchCurFile,COUNTOF(g_wchCurFile)))
       {
         DWORD dwFileAttributes = GetFileAttributes(g_wchCurFile);
diff --git a/src/Notepad3.rc b/src/Notepad3.rc
index 7bf54c0f9..d4c800e7f 100644
--- a/src/Notepad3.rc
+++ b/src/Notepad3.rc
@@ -699,7 +699,7 @@ BEGIN
     CONTROL         "<a>(?)</a>",IDC_BACKSLASHHELP,"SysLink",0x0,106,73,14,10
     CONTROL         "<a>(?)</a>",IDC_WILDCARDHELP,"SysLink",0x0,191,85,14,10
     CONTROL         "",IDS_FR_STATUS_TEXT,"Static",SS_LEFTNOWORDWRAP,7,117,259,9,WS_EX_STATICEDGE
-    PUSHBUTTON      "Toggle Visibility",IDC_TOGGLE_VISIBILITY,211,65,55,14
+    PUSHBUTTON      "Toggle &Visibility",IDC_TOGGLE_VISIBILITY,211,65,55,14
 END
 
 IDD_REPLACE DIALOGEX 0, 0, 273, 156
@@ -734,7 +734,7 @@ BEGIN
     CONTROL         "<a>(?)</a>",IDC_REGEXPHELP,"SysLink",0x0,107,114,14,10
     CONTROL         "<a>(?)</a>",IDC_WILDCARDHELP,"SysLink",0x0,191,114,14,10
     CONTROL         "",IDS_FR_STATUS_TEXT,"Static",SS_LEFTNOWORDWRAP,7,144,259,9,WS_EX_STATICEDGE
-    PUSHBUTTON      "Toggle Visibility",IDC_TOGGLE_VISIBILITY,211,94,55,14
+    PUSHBUTTON      "Toggle &Visibility",IDC_TOGGLE_VISIBILITY,211,94,55,14
 END
 
 IDD_RUN DIALOGEX 0, 0, 229, 96
diff --git a/src/Styles.c b/src/Styles.c
index 11791be3b..e40bd34eb 100644
--- a/src/Styles.c
+++ b/src/Styles.c
@@ -125,7 +125,8 @@ enum LexDefaultStyles {
   STY_BOOK_MARK = 12,
   STY_MARK_OCC = 13,
   STY_URL_HOTSPOT = 14,
-  STY_INVISIBLE = 15
+  STY_INVISIBLE = 15,
+  STY_READONLY = 16
 };
 
 
@@ -3933,6 +3934,26 @@ void Style_SetInvisible(HWND hwnd, bool bInvisible)
 
 
 
+//=============================================================================
+//
+//  Style_GetReadonlyStyleID()
+//
+int Style_GetReadonlyStyleID()
+{
+  return (STYLE_LASTPREDEFINED + STY_READONLY);
+}
+
+
+//=============================================================================
+//
+//  Style_SetInvisible()
+//
+void Style_SetReadonly(HWND hwnd, bool bReadonly)
+{
+  SendMessage(hwnd, SCI_STYLESETCHANGEABLE, Style_GetReadonlyStyleID(), (LPARAM)!bReadonly);
+}
+
+
 //=============================================================================
 //
 //  Style_SetLongLineColors()
diff --git a/src/Styles.h b/src/Styles.h
index 95fee565f..774acd93e 100644
--- a/src/Styles.h
+++ b/src/Styles.h
@@ -72,6 +72,7 @@ bool   Style_Export(HWND);
 void   Style_SetLexer(HWND,PEDITLEXER);
 void   Style_SetUrlHotSpot(HWND, bool);
 void   Style_SetInvisible(HWND, bool);
+void   Style_SetReadonly(HWND, bool);
 void   Style_SetLongLineColors(HWND);
 void   Style_SetCurrentLineBackground(HWND, bool);
 void   Style_SetFolding(HWND, bool);
@@ -118,6 +119,7 @@ INT_PTR CALLBACK Style_SelectLexerDlgProc(HWND,UINT,WPARAM,LPARAM);
 void   Style_SelectLexerDlg(HWND);
 int    Style_GetHotspotStyleID();
 int    Style_GetInvisibleStyleID();
+int    Style_GetReadonlyStyleID();
 bool   Style_StrGetWeightValue(LPCWSTR,int*);
 void   Style_AppendWeightStr(LPWSTR, int, int);