restore a working 'find' structure

notebook/static/notebook/js/outputarea.js

@@ -650,8 +650,9 @@ define([
         var type = 'image/svg+xml';
         var toinsert = this.create_output_subarea(md, "output_svg", type);
 
-        // Get the svg element from within the HTML.
-        var svg = $('<svg \>').html(svg_html);
+        // Get the svg element from within the HTML. 
+        // One svg is supposed, but could embed other nested svgs
+        var svg = $($('<div \>').html(svg_html).find('svg')[0]);
         var svg_area = $('<div />');
         var width = svg.attr('width');
         var height = svg.attr('height');