I tried to figure out how to use the <r:mailer:if_success>-tag, but
couldn't find any effect no matter where I put it in the form
template... and no matter what I used as a redirect_to (I also tried
without one and having the form page as the redirect_to page).
I used it like this: <r:mailer:if_success>Thanks!</r:mailer:if_success>
Another thing that I noticed is that there's no real explanation to
how you call variables in the email templates: http://github.com/radiant/radiant-mailer-extension/tree/master
...apart from <r:mailer:get name="" /> showing up in the list of
tags that can be used in the form, which isn't really accurate.
However I figured this one out by looking in the comments in the code,
as the handbook recommends. :)
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