I have previously stated this months ago in the IRC, and have found
some references in other bug report forums including Debian, Ubuntu,
and FreeBSD, but I have been unable to find a solution for my own
problem. The proposed solutions include "Don't use Tor", "Use Dante",
and the classic "Nevermind, I figured it out!"

The problem I have been having since November 2018 when I upgraded to
ASCII was that I simply can not torify Fetchmail. I later discovered
that Mutt is affected. The problem seems to be related to my mail
spool, /var/mail/se7en.

Fetchmail properly downloads the files when torified. The problem is
when it attempts to write them to /var/mail/se7en. The output of a
torify'd `fetchmail -v` is

fetchmail: MDA error while fetching from se7en@???@mail.cock.li
fetchmail: 6.3.26 querying mail.cock.li (protocol IMAP) at Tue 14 May
2019 11:21:55 PM PDT: poll completed
fetchmail: Query status=6 (IOERR)
fetchmail: normal termination, status 6

Btw, these are the permissions of my /var/mail/

-rw-rw---- 1 se7en mail 2.8M May 14 23:09 se7en

When I attempt to torify mutt (which was part of my previous setup) it
produces an error saying "/usr/bin/mutt_dotlock: Operation Not
Permitted". (Part of the error is cut off). I can then view my spool's
mail, but I can not change the flags or compose a new message.

None of these problems occur in a non-tor environment. Is the problem
relating to you, Debian Packaging, Tor, Mutt, Fetchmail, or what?

Torifying MSMTP works. Torifying almost all-else works. It is only
seemingly related to my Procmail+Fetchmail setup.

Does /anyone/ have a solution? It has been too long to have such a
seemingly-simple problem I can not find a solution to rectify!

-- 
|-----/                   | Se7en
     /  The One and Only! | se7en@???
    /                     | 0x73518A15BA3C1476
   /                      | Website TBA