Emails page in the form build mode is crashing

Whenever i now go to the settings of a form to change the emails settings for auto responder message etc, the page crashes. This happens in different browsers such as Google Chrome as well as Internet Explorer. There is a message on IE that says page is not repsonding due to a long running script which when i stop i can only then see and use the page UI again.

But if i then edit the response it will not save it or allow test email to be sent.

I am able to replicate the issue at my end with the cloned version of your form as well. Could you try creating a new notification to the form and see if that works normally?

Please get back to us if you need any further assistance. We will be happy to help.