Email Form Success not displaying in Designer

Hello all,
I built a webform and followed the tutorial on how to edit the success and error messages. When I click on the Success tab in settings of the Form Block element, I do not see the corresponding div block. They remain in their hidden state. What am I missing? The tutorial must be older because it does not have the Form Block element but rather a DIV wrapper.

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I looked at your form and was surprised I was not able to switch between states even when fiddling with the layout. I added another form and had no issues so It is not the site.

So my recommendation is to recreate the form. Checking along the way. If the problem manifests itself again, at least you may have a cause, which would be helpful on a bug report.

I did some experimenting and I found that if you place any other element such as a Header in the Form Block, it breaks the hidden elements. So I took the H3 out and nested it with Form Block into a DIV. Solved.