Most of my mail comes from the 50MLs i'm subscribed to. Unfortunately some MUAs suck that much, they don't even respond in threads. My idea how to fix them would be: $ notmuch search subject:Foo and from douche@brokenwebmua.com thread:00000000000003ff [..] douche@brokenwebmua.com,me Foo thread:00000000000003cb [..] douche@brokenwebmua.com,me Re:Foo thread:00000000000003cd [..] douche@brokenwebmua.com,me Re:Foo thread:00000000000003c7 [..] douche@brokenwebmua.com,me Re:Foo $ notmuch thread-align subject:Foo and from:douche@brokenwebmua.com aligned 4 threads $ notmuch search subject:Foo and from douche@brokenwebmua.com thread:00000000000003dd [..] Foo That of course makes the optimistic assumption, that the douche in question did actually change the subject when he changed the topic, and has the date: field set properly. At least in my case that's true. Thoughts?