I've noticed several mailing lists send me "you're not reading our mail, we're going to unsubscribe you" messages because I don't allow my MUA to spy for them.

I've noticed several mailing lists send me "you're not reading our mail, we're going to unsubscribe you" messages because I don't allow my MUA to spy for them. Fixed; created a cron job to curl relevant tracking pixels once a month.