Can't edit Panels content When trying to change the Panel content design, there are no controls displayed as shown:



This is happening only when using Charts in my Panel page. I got this error chrome inspector console:

Uncaught SyntaxError: Unexpected token , in JSON at position 6
    at JSON.parse (&lt;anonymous&gt;)
    at Function.parseJSON (jquery.js?v=1.4.4:32)
    at HTMLDivElement.&lt;anonymous&gt; (charts_highcharts.js?v=1.0:11)
    at Function.each (jquery.js?v=1.4.4:34)
    at $.fn.init.each (jquery.js?v=1.4.4:27)
    at $.fn.init.$.fn.once (jquery.once.js?v=1.2:55)
    at Object.Drupal.behaviors.chartsHighcharts.attach (charts_highcharts.js?v=1.0:9)
    at Object.&lt;anonymous&gt; (drupal.js?pj2bso:112)
    at Function.each (jquery.js?v=1.4.4:33)
    at Object.Drupal.attachBehaviors (drupal.js?pj2bso:110)
parseJSON @ jquery.js?v=1.4.4:32
(anonymous) @ charts_highcharts.js?v=1.0:11
each @ jquery.js?v=1.4.4:34
each @ jquery.js?v=1.4.4:27
$.fn.once @ jquery.once.js?v=1.2:55
Drupal.behaviors.chartsHighcharts.attach @ charts_highcharts.js?v=1.0:9
(anonymous) @ drupal.js?pj2bso:112
each @ jquery.js?v=1.4.4:33
Drupal.attachBehaviors @ drupal.js?pj2bso:110
(anonymous) @ drupal.js?pj2bso:593
ready @ jquery.js?v=1.4.4:30
u @ jquery.js?v=1.4.4:38
Found the solution here: can't edit panels page with highcharts chart in quicktab (w/ workaround)