Those fixes should work as expected for sure, but i see them as a pretty much wrong way of doing it (adding new additional fields and so on) cause it wont resolve the problem for other similar cases (other prefixes etc).
Sadly to admit, but we still use non-ajax forms. If we wont do so i would recommend fixing this problem just by sending form id along with the form data and back again with response. In such way we could have this problem eliminated and configs left clean, with no additional fields.