Comment 44 for bug 885525

Hm, the general solution could be to add a pref in imap "Advanced..." that would disable x-list per server (there's another bug to allow disabling it). And disable folder selection if that pref isn't set and x-list is supported for the server.
You'd anyway get the initial correct folders set up and after you disable x-list you can do whatever you need, for whatever special purposes.