+The time-based conditions use as reference the time indicated in the
+heading From line, and not in the Date: field.
+
+.TP
+\fBf <regexp>\fR (from)
+selects mails whose leading line From, or fields From:, Sender:,
+Reply-To:, or Return-Path: matches the regexp.
+.TP
+\fBt <regexp>\fR (to)
+selects mails whose field To:, Cc:, or Bcc: matches the regexp.