[codetrotter]

One variant that seemed interesting was method=get with enctype=application/x-www-form-urlencoded

In this case the values from the form get added as headers in the email so they are not directly visible to the user

I thought that I could still add user-visible subject and body by adding ?subject=foo&body=bar to the mailto: url

For example I could then have the subject say "Web form submission", and have the body of the mail contain a description that tells the user to send the email and that the data they filled into the form will be sent along with the email.

Even that is not great UX imo, but could still be interesting.

However from my testing with Brave web browser and Apple Mail, the subject and body are not filled in for the user in this case.