-----------------
- Hidden form response iframe gets created on the fly and removed after form
processing. This is necessary to prevent a useless entry in browser history.
WARNING: This change breaks the server implementation. Take a look at
Ajax forms documentation how to adopt your code to this change. Also make
sure to remove the hidden iframe from bdajax markup if you don't use the
templates shipped with this package.
[rnix, 2017-09-12]