$ emacs -Q random.zip

1. Switch to buffer "*scratch*"
2. Type "P" (without quotes)
3. Press M-/
4. Here it finds expansion "PK" from buffer "random.zip".  Cycling
   with M-/ finds a few more, which are more binary-like.

On Tue, 13 Jul 2021 at 21:14, Lars Ingebrigtsen <larsi@gnus.org> wrote:

Paul Pogonyshev <pogonyshev@gmail.com> writes:

> Apparently not from tarballs anymore, but still e.g. from a `.zip'
> archive. Though I have Emacs 27.1 here, not 28.

I tried visiting a zip file here now (in Emacs 27.1), but I was unable
to make dabbrev-expand expand to any of the strings in the raw zip file.

Do you have a recipe, starting from "emacs -Q", to reproduce the bug?
(Including a test zip file, I guess.)

--
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no