I would like to bring your attention to a future enhancement.
File Upload with Forms: Once a user attaches a file, it gets uploaded before the user hits the form submission button. Message appears that file was successfully uploaded even though form hasn’t been submitted.
Also, a user can try to upload a file that is over the 50mg limit. A message appears that the file is over the limit. The form can still be submitted, appearing as if the file also uploaded.
Hope the information is useful.