Ah, ok, that sounds reasonable. You want only a link or something similar to have a switch for the user to select the HTTP- or the HTTPS-login.

Exactly! Just an option to switch to the HTTPS type posts/links/logins.

But, if your forum is accessible via HTTPS, why not only via HTTPS? This would be consquent.

Speed! :) HTTPS is slower. But posting only the login datas via HTTPS is acceptable.

"Only HTTPS" everywhere on the forum is also a good idea, though. The priority/importance of speed or security, depends on the user, of course.

So such an optional feature would be nice.

regards.