only append modal to dom if not already present

js/bootstrap-modal.js

@@ -51,8 +51,9 @@
         backdrop.call(this, function () {
           var transition = $.support.transition && that.$element.hasClass('fade')
 
+          !that.$element.parent() && that.$element.appendTo(document.body) //don't move modals dom position
+
           that.$element
-            .appendTo(document.body)
             .show()
 
           if (transition) {