--- a/widget/cocoa/TextInputHandler.h
+++ b/widget/cocoa/TextInputHandler.h
@@ -808,16 +808,17 @@ public:
                       void* aData) override;
 
 public:
   virtual bool OnDestroyWidget(nsChildView* aDestroyingWidget) override;
 
   virtual void OnFocusChangeInGecko(bool aFocus);
 
   void OnSelectionChange(const IMENotification& aIMENotification);
+  void OnLayoutChange();
 
   /**
    * Call [NSTextInputContext handleEvent] for mouse event support of IME
    */
   bool OnHandleEvent(NSEvent* aEvent);
 
   /**
    * SetMarkedText() is a handler of setMarkedText of NSTextInput.

--- a/widget/cocoa/TextInputHandler.mm
+++ b/widget/cocoa/TextInputHandler.mm
@@ -2767,16 +2767,19 @@ IMEInputHandler::NotifyIME(TextEventDisp
       OnFocusChangeInGecko(true);
       return NS_OK;
     case NOTIFY_IME_OF_BLUR:
       OnFocusChangeInGecko(false);
       return NS_OK;
     case NOTIFY_IME_OF_SELECTION_CHANGE:
       OnSelectionChange(aNotification);
       return NS_OK;
+    case NOTIFY_IME_OF_POSITION_CHANGE:
+      OnLayoutChange();
+      return NS_OK;
     default:
       return NS_ERROR_NOT_IMPLEMENTED;
   }
 }
 
 NS_IMETHODIMP_(IMENotificationRequests)
 IMEInputHandler::GetIMENotificationRequests()
 {
@@ -4265,16 +4268,30 @@ IMEInputHandler::OnSelectionChange(const
   mRangeForWritingMode =
     NSMakeRange(aIMENotification.mSelectionChangeData.mOffset,
                 aIMENotification.mSelectionChangeData.Length());
   if (mIMEHasFocus) {
     mSelectedRange = mRangeForWritingMode;
   }
 }
 
+void
+IMEInputHandler::OnLayoutChange()
+{
+  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+
+  if (!IsFocused()) {
+    return;
+  }
+  NSTextInputContext* inputContext = [mView inputContext];
+  [inputContext invalidateCharacterCoordinates];
+
+  NS_OBJC_END_TRY_ABORT_BLOCK;
+}
+
 bool
 IMEInputHandler::OnHandleEvent(NSEvent* aEvent)
 {
   if (!IsFocused()) {
     return false;
   }
   NSTextInputContext* inputContext = [mView inputContext];
   return [inputContext handleEvent:aEvent];