Comment 45 for bug 885525

(In reply to Magnus Melin from comment #41)
> 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 seems claiming that general/final/absolutely correct/sufficient/perferct/... , solution is mandatory...
I'm merely proposing a practical solution what keeps "Forcing of [Gmail]/IMAP as trash for majority of general Gmail IMAP && Tb users" without rejecting request of "using other than [Gmail]/IMAP as trash of Tb" from matured users who understand Gmail/Gmail IMAP well...

If perfect solution is needed for this bug for "trash in Gmail IMAP" only, I believe this bug is better closed as dup of bug 800035 what requests perferct solution in bug 800035 comment #2 for any of Trash, Junk, Archive, and Drafts/Sent.