diff --git a/src/gui/editing.cpp b/src/gui/editing.cpp
index ea12eb591..f299b1af2 100644
--- a/src/gui/editing.cpp
+++ b/src/gui/editing.cpp
@@ -66,6 +66,8 @@ void FurnaceGUI::prepareUndo(ActionType action) {
         e->curPat[i].getPattern(e->curOrders->ord[i][curOrder],false)->copyOn(oldPat[i]);
       }
       break;
+    case GUI_UNDO_REPLACE: // this is handled by doReplace()
+      break;
   }
 }
 
@@ -86,7 +88,7 @@ void FurnaceGUI::makeUndo(ActionType action) {
           if (oldOrders.ord[i][j]!=e->curOrders->ord[i][j]) {
             s.ord.push_back(UndoOrderData(subSong,i,j,oldOrders.ord[i][j],e->curOrders->ord[i][j]));
           }
-        }
+        }SATGDIOPTASDIOKP;ASDTG
       }
       s.oldOrdersLen=oldOrdersLen;
       s.newOrdersLen=e->curSubSong->ordersLen;
@@ -126,6 +128,8 @@ void FurnaceGUI::makeUndo(ActionType action) {
         doPush=true;
       }
       break;
+    case GUI_UNDO_REPLACE: // this is handled by doReplace()
+      break;
   }
   if (doPush) {
     MARK_MODIFIED;
@@ -943,6 +947,7 @@ void FurnaceGUI::doUndo() {
     case GUI_UNDO_PATTERN_FLIP:
     case GUI_UNDO_PATTERN_COLLAPSE:
     case GUI_UNDO_PATTERN_EXPAND:
+    case GUI_UNDO_REPLACE:
       for (UndoPatternData& i: us.pat) {
         e->changeSongP(i.subSong);
         DivPattern* p=e->curPat[i.chan].getPattern(i.pat,true);
@@ -991,6 +996,7 @@ void FurnaceGUI::doRedo() {
     case GUI_UNDO_PATTERN_FLIP:
     case GUI_UNDO_PATTERN_COLLAPSE:
     case GUI_UNDO_PATTERN_EXPAND:
+    case GUI_UNDO_REPLACE:
       for (UndoPatternData& i: us.pat) {
         e->changeSongP(i.subSong);
         DivPattern* p=e->curPat[i.chan].getPattern(i.pat,true);
diff --git a/src/gui/findReplace.cpp b/src/gui/findReplace.cpp
index d5548c0fb..5dae95bc5 100644
--- a/src/gui/findReplace.cpp
+++ b/src/gui/findReplace.cpp
@@ -189,6 +189,12 @@ void FurnaceGUI::doFind() {
   queryViewingResults=true;
 }
 
+/* issues with the find and replace function:
+   - doesn't mark the module as modified
+   - can't undo
+   - replace notes to anything starting from C-0 to lower notes will have an octave higher, so set it to replace to C-0 it will becom C-1, b_1 will become B-0 and so on
+*/
+
 void FurnaceGUI::doReplace() {
   doFind();
   queryViewingResults=false;
@@ -399,6 +405,10 @@ void FurnaceGUI::doReplace() {
   for (int i=0; i<DIV_MAX_CHANS; i++) {
     if (touched[i]!=NULL) delete[] touched[i];
   }
+
+  if (!curQueryResults.empty()) {
+    MARK_MODIFIED;
+  }
 }
 
 #define FIRST_VISIBLE(x) (x==GUI_QUERY_MATCH || x==GUI_QUERY_MATCH_NOT || x==GUI_QUERY_RANGE || x==GUI_QUERY_RANGE_NOT)
diff --git a/src/gui/gui.h b/src/gui/gui.h
index e5ad4a943..9381bab09 100644
--- a/src/gui/gui.h
+++ b/src/gui/gui.h
@@ -566,7 +566,8 @@ enum ActionType {
   GUI_UNDO_PATTERN_INVERT_VAL,
   GUI_UNDO_PATTERN_FLIP,
   GUI_UNDO_PATTERN_COLLAPSE,
-  GUI_UNDO_PATTERN_EXPAND
+  GUI_UNDO_PATTERN_EXPAND,
+  GUI_UNDO_REPLACE
 };
 
 struct UndoPatternData {