Mu 1.7.23 Causing Maildir Corruption - 26/06/2022 00:00 GMT

Development versions of mu between 1.7.18 and 1.7.25 (only 1.7.23 was ever
packaged in Gentoo) have a bug causing mail file names to sometimes get mangled
after moving messages between directories. Symptoms include unread messages
never being marked as read.

Affected messages have the ':2,' flag appended multiple times. Using the
following commands, users can remove the extra flags.

    find ~/Maildir -name '*:2,*:*' |
      sed "s/\(\([^:]*\)\(:2,\)\\(:2,.*$\)\)/mv '\0' '\2\4'/" \
      > rename.sh
    # review rename.sh. empty file indicates that you are unaffected
    sh rename.sh

Upstream issue: https://github.com/djcb/mu/issues/2268