[pmwiki-users] how to hide sidebar when login form is displayed?

[SteP]

How can I hide the left sitebar when the login form is being displayed?

I want to show just the contents of Site.AuthForm but nothing else. Is 
this possible?

I suspect it can't be done with markup alone. I tested an unconditional 
(:noleft:) in triad and fixflow skins, but Page?action=login still had a 
visible sidebar.