+A Maildir to watch for confirmed spam messages to appear in.
+Messages which appear in this folder with the (S)een flag
+will be hidden from all configured inboxes based on Message-ID
+and content matching.
+
+Messages without the (S)een flag are not considered for hiding.
+This hiding affects all configured public-inboxes in PI_CONFIG.
+
+As with C<publicinbox.$NAME.watch>, C<imap://> and C<imaps://> URLs
+are supported in public-inbox 1.6.0.