Hi,

new messages are given a default (configurable) tag, typically /new/ …
This is handy for automatic tagging.

What about another automatic tag to re-add to an existing mail when =notmuch new= detect a moved, renamed or reflagged message … 
This would allow something like tag synchro through an =IMAP= mailbox, or at least keep folder and tag organization coherent while a message is moved …

my usecase is :
- On PC A
  - message /1/ is received from =IMAP= in default mail folder, given tag /new/
  - message /1/ is automatically tagged /inbox/ (see /afew/)
- On PC B
  - message /1/ is received from =IMAP= in default mail folder, given tag /new/
  - message /1/ is automatically tagged /inbox/ (see /afew/)
  - manual tagging into mail client as /archive/
  - mail is moved (see /afew/) to /Archives/ folder due to /archive/ tag
  - message /1/ no more in default but /Archives/ folder is synchronized back to =IMAP= server
- On PC A (not possible today)
  - message /1/ is re-received from =IMAP= in /Archives/ folder, and removed from default mail folder, added tag /renew/
    - (today, =notmuch new= just detect the moved file, and thanksfully keep existing tags)
  - message /1/ is automatically tagged /archive/ due to presence in /Archives/ folder (and /renew/ tag)

Thank you,

-- 
~~^v^~~ Baptiste