How to reproduce it :

• I use the classified ads plugin
• I try to create a new content from FO
• I submit the form
• I get this error in the console :

  5960327147246548:9 Uncaught TypeError: window.parent.result_5960327147246548 is not a function

• Then, I refresh again the first page with debug.mode=super at the end of the url
• I submit again my content
• The content is submitted with succes.