Fix #18437

Author: CubikingChill

src/context/internal/globalcontext.cpp

@@ -95,6 +95,16 @@ void GlobalContext::doSetCurrentNotation(const INotationPtr& notation)
         return;
     }
 
+    // End note input on the outgoing notation to prevent stale InputState
+    // that can cause corruption when notes are entered on the new notation
+    // and propagated back via linked clones (see #18437)
+    if (m_currentNotation) {
+        auto noteInput = m_currentNotation->interaction()->noteInput();
+        if (noteInput->isNoteInputMode()) {
+            noteInput->endNoteInput(false);
+        }
+    }
+
     m_currentNotation = notation;
 
     if (m_currentNotation) {

src/engraving/dom/segment.cpp

@@ -871,7 +871,13 @@ void Segment::remove(EngravingItem* el)
     case ElementType::CHORD:
     case ElementType::REST:
     {
-        m_elist[track] = 0;
+        // Only clear the slot if it actually holds the element being removed.
+        // During linked-score propagation, an AddElement for a new ChordRest may
+        // have already overwritten this slot; blindly zeroing it would silently
+        // discard the new element and leave a gap in voice 0 (see #18437).
+        if (m_elist[track] == el) {
+            m_elist[track] = 0;
+        }
         staff_idx_t staffIdx = el->staffIdx();
         measure()->checkMultiVoices(staffIdx);
         // spanners with this cr as start or end element will need relayout
@@ -898,7 +904,9 @@ void Segment::remove(EngravingItem* el)
     case ElementType::MMREST:
     case ElementType::MEASURE_REPEAT:
     case ElementType::TIME_TICK_ANCHOR:
-        m_elist[track] = 0;
+        if (m_elist[track] == el) {
+            m_elist[track] = 0;
+        }
         break;
 
     case ElementType::HARMONY:
@@ -962,12 +970,16 @@ void Segment::remove(EngravingItem* el)
         break;
 
     case ElementType::TIMESIG:
-        m_elist[track] = 0;
+        if (m_elist[track] == el) {
+            m_elist[track] = 0;
+        }
         el->staff()->removeTimeSig(toTimeSig(el));
         break;
 
     case ElementType::KEYSIG:
-        m_elist[track] = 0;
+        if (m_elist[track] == el) {
+            m_elist[track] = 0;
+        }
         if (!el->generated()) {
             el->staff()->removeKey(tick());
         }
@@ -980,11 +992,15 @@ void Segment::remove(EngravingItem* el)
 
     case ElementType::BAR_LINE:
     case ElementType::AMBITUS:
-        m_elist[track] = 0;
+        if (m_elist[track] == el) {
+            m_elist[track] = 0;
+        }
         break;
 
     case ElementType::BREATH:
-        m_elist[track] = 0;
+        if (m_elist[track] == el) {
+            m_elist[track] = 0;
+        }
         score()->setPause(tick(), 0);
         break;