Subsequent form submits don't display returned message

[altr]

Subsequent form submits don't display returned message anymore
When submitting a form the first time everything works as expected (messages are displayed properly). However, subsequent submits don't show the returned message anymore. The field errors are shown but not the message.

Additional observations
The information is returned from the server side and can be read in the browser dev tools

Reproduction
https://stackblitz.com/edit/sveltejs-kit-template-default-quvzoff6

1. Click on the Superforms link at the top
2. Submit the form
3. See how the message from the server is displayed
4. Submit the form again
5. See that the message from the server disappears. Expected behaviour is that the message stays as it's still the same form information as before.

[ciscoheat]

Duplicate of #536 , check that issue for updates.