MailForms don't work on the public page of private sites (usually system:join).
When the password or apply options aren't perfect for the website owner's needs, it would be better if they could use a MailForm on the page to get people to e-mail them an application (using additional fields where necessary instead of the single field that applying for membership usually gives the user).
Problem: MailForms on private sites currently give this error message: "This Site is private and accessible only to its members."
The wish: That MailForms would work on the public page of a private site (e.g. system:join)
Concept of "public" page on private site is very limited. I'd go for more complete support for private categories for public sites.
As a dirty workaround I can only suggest a MailForm on a separate public site and a redirect on system:join of the private site to that page (or an iframe with the MailForm inside).
Piotr Gabryjeluk
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