Duplicate avoidance?

[David A. <da...@bo...>]

I just set up my Gnus to put a copy of every message I send into my
local "All Mail" box.  GMail already puts a copy in my remote "All Mail"
box.  Then I ran mbsync, and didn't see the message twice in my local
"All Mail."  Did I get lucky, or does mbsync have a way to avoid
generating duplicates of a message when it appears, via other means, in
both local and remote mailboxes?  Is this in fact just one more
testament to mbsync's total awesomeness?

-- 
Dave Abrahams
BoostPro Computing                  Software Development        Training
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