Redirect after initial signup

It would be very helpful to be able to specify a redirect page following member registration.  Especially for organizations that do not auto-approve members, at this point the member is in a sort of "limbo" and can't really do anything.  Our concern is that members will try to login, and be annoyed/confused when that doesn't work, or will attempt to create their account again, which will also be confusing/annoying.

It looks like support for this is *almost* there, or at least this snip from the widget embed code looks promising, but we've not been able to get it to do anything:

function(e) { switch (e.data.action) { case "setHeight": { document.getElementById('form-iframe').height = (e.data.height) + "px"; break; } case "redirectAfterLogin": { var url = e.data.urlToRedirect; location.href.url = url; break; } }

FWIW, this is the landing page we'd like to be able to display:  https://www.berkeleytennis.com/post-signup