[Users] upgrade from 3.9.3 to 3.12

[Andrej Kacian]

On Mon, 26 Oct 2015 19:36:04 +0100
<c.buhtz at posteo.jp> wrote:

> Is there any difference in the "data structure" (I mean the mail-
> and box-folder) between that two versions?

I think there have been some additions to clawsrc and accountrc, but I
do not remember anything that would cause incompatibility. Note,
however, that 3.9.3 is almost three years old by now, so your best bet
is combination of:
a) review changelogs and/or release notes of all versions in between
   (a web search for "unleashed site:lists.claws-mail.org" should do the
   trick)
b) back up your folders before trying anything

Regards,
-- 
Andrej