Subject: not always, but sometimes

From: 積丹尼 Dan Jacobson <[email-masked]>
Date: Mon, 29 Feb 2016 08:09:00 +0800

It seems that
   E runs the command gnus-summary-mark-as-expirable
usually works.
The article and its subject line in the index are deleted after a week.
But occasionally the subject line of some articles remain in the index.