I was getting this issue with a project we have been working on, so I tried it with a blank .story file and got the same result.
Create a slide with radio button controls (I put in two).
Convert to Freeform Interaction, Pick Many.
Form View displays. Add the radio buttons as Choices.
Set the Score to None.
When I run the file, if I don't select anything and Submit, I get the "required" popup, as expected. But if I select one of the radio buttons and Submit, I do not get the Thank You popup. I cannot seem to trigger the Thank You popup at all.
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