Just in case you don’t have your own index of the 10+ million messages in Apache mailing list archives, this is the site for you.
😉
I ran across it today while debugging an error in a Solr config file.
If I could add one thing to MarkMail it would be software release date facets. Posts are not limited by release dates but I suspect a majority of posts between release dates are about the current release. Enough so that I would find it a useful facet.
You?