hi!
1-----
Ask a question : Question minimum length - is 50 anyway, and it don't can change (if in configuration is set 1-50)
in Shopfront at the page ASK a question if length <50 than wrote message "Some fields are incorrect, check the filling"
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at the page "Thank you for your order" by guest order : message:
You must specify at least one recipient email address.
Info: message sent : , user@domain.com
Invalid address: Invalid address: