$(link-login) == $(link-login-only) ?

I tried to introduce a special page after successful login to hotspot, by modifying login.html:

This works, my.html is displayed in browser, BUT:

Within “my.html”, $(link-login) now is identical to $(link-login-only), so the original URL is lost.
However, within alogin.html, is is still intact.

Is this a bug or a feature ?