Marketplace: Message "No package file submitted" after submitting an unaccepted file format or an empty .zip

Steps:

1. Go to the Marketplace (UAT)
2. Log in as a Connect subscriber
3. Scroll down and click “Add your package to the Marketplace”
4. Choose a file of a different format than .zip or an empty .zip

Expected result:

There's a message explaining why the file wasn't accepted, and the message should be red (or different from other texts)

Actual result:

The page refreshes and a message "No package file submitted" is displayed (see video)