@Override
      protected void handleMouseClick() {
        if (!myChange.isValid()) return;
        final Project project = myViewer.getProject();
        final Document document = myViewer.getEditor(sourceSide.other()).getDocument();
        DiffUtil.executeWriteCommand(document, project, DiffBundle.message("message.replace.change.command"), perform);
      }
@Override
      protected void handleMouseClick()