A. Dumas  wrote:
> I can't check anymore because I do have one (indeed, Exim) as a dependency
> of the scheduler 'at' which I installed manually. This was from a fresh
> Buster install and it only came when I installed 'at' [...]
>
>> When I found it I assumed it was there to keep RPi4 folks happy if they
>> were expecting to use one as a cheap desktop Linux box.
>
> Meh. Thunderbird or other GUI mail clients work just like their Win/Mac
> counterparts: they connect to the mail server themselves so don't need or
> use an MTA.

Oh! I do have another Buster install without at. No MTA there. The GUI mail
client is claws-mail.

Packages that explicitly depend on exim4 listed below. It's not exhaustive
"anything that might install exim", e.g. at is not listed because it picks
a  but I have no idea how it decides, maybe simply the first
available from its own list.

$ apt-cache rdepends exim4
exim4
Reverse Depends:
  alpine
 |fex
 |gitlab
 |whatsnewfm
 |vzdump
 |vm
 |uucp
 |uqwk-spool
 |uqwk
 |typo3-src-4.5
 |typo3-dummy
 |tkrat
 |systraq
 |systemd-cron
 |sxid
 |sauce
 |rt4-clients
  rmail
 |ripit
 |reportbug
 |renattach
  prayer-accountd
  postgrey
 |popa3d
 |pop-before-smtp
 |phpbb3
 |owncloud
 |movabletype-opensource
 |mlmmj
 |mailto
 |mailgraph
 |maildrop
 |mailagent
 |killer
 |ipband
  greylistd
 |gotmail
 |gnats-user
 |gnats
 |geximon
 |debsecan
 |debbugs
 |debarchiver
 |darcs-monitor
 |broctl
  bley
 |biabam
 |backuppc

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