Adds recipient query string details to hyperlinks.
This filter is meant for use inside e-mail templates. It replaces each
## with the details of the subscriber that the mail
is sent to, encoded as query string arguments.
Each occurrence of
## will be transformed to recipient details in
the following form:
Its use case is when sending a mailing with a link in it which arrives at a webpage where the user has to enter his e-mail address and name details. Using this filter, those parameters can be conveniently be pre-filled.