Description

This was all introduced by the original project author early on (April 2015), no explanation for it. Seems safe to remove.

• None of the paths they use as argv values exist.
• uucp doesn't seem relevant to the project. No justification for it, no issues or PRs in project history or codebase.
• mailman is for managing mailing lists, we do have issues requesting support in May 2020 and Nov 2016. Debian 11 Bullseye also no longer includes a mailman package, there is mailman3 and mailman3-full, assuming anyone wants to add that, they can add the assumed required master.cf line back and any other configuration they need, we don't officially support such.
• Postfix has a guide for setup with maildrop, this is different from the maildrop queue in /var/spool/postfix/maildrop that postdrop handles AFAIK. Especially since we can see the guide advises setting virtual_transport to maildrop which we have already configured to be LMTP with Dovecot. As the binary itself doesn't exist at the configured path, if this ever worked it hasn't been for a while presumably.. and no issue or PR github tracker history, nor content in the project files.
• An issue raised by original project author does mention scalemail briefly via log failure, that was back in Sep 2016, I don't know what the setup was like back then and perhaps this was something that was in the image prior to transition to Debian, or they added it themselves. The issue was regarding permissions with ONE_DIR ENV, that was AFAIK resolved via the chown -R fixes script.
  I have not looked through anything else in master.cf, just housekeeping.

Type of change

• Improvement (non-breaking change that does improve existing functionality)

Not likely:

• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (README.md or the documentation under docs/)
• If necessary I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes