Create a sign-up for an open gift exchange
Edit your offers via the "Edit Prompt" button on the "My Signup" page in such a way that it no longer meets the challenge's criteria
Select the "Update" button
Nothing. The page reloads in its edit state, with the changes made reflected, but no error message is made and the edit isn't applied
If you do the same thing on the Requests version of "Edit Prompt" you get a red flash error message describing what element no longer meets its criteria. This should also happen on the Offers.