Dear Maintainer,

I routinely upgrade packages by a series of commands like
  apt-get install $(apt-mark showmanual | grep ^lib[abcde])
, changing the regex pattern from one command to the next to upgrade a
chunk of installed packages at a time.

The most recent time I did so with that specific command, at the end of
the list was a series of binNMU entries, as normal.

In this instance, that list included the following two entries:

====1====
--- Binary NMU of: e2fsprogs (1.47.2-3+b4), libcap2 (1:2.75-10+b2)

  * Binary-only non-maintainer upload for amd64; no source changes.
  * Rebuild for outdated Built-Using (glibc/2.41-11)
====1====

====2====
--- Binary NMU of: libcap2 (1:2.75-10+b2), e2fsprogs (1.47.2-3+b4)

  * Binary-only non-maintainer upload for i386; no source changes.
  * Rebuild for outdated Built-Using (glibc/2.41-11)
====2====

As far as I can see, these appear to cover the exact same NMU twice,
except with the packages listed in reverse order the second time. I
expected that each binNMU would have only one entry shown, and that the
order of packages within an entry would not matter for determining
whether it would be considered a duplicate.

I do not know how this behavior came about, but it seems clear that it
would not be intended, so I want to at least report that it occurred.