bug#66330: 28.2; Gnus wide reply (S W) changes Subject header when used from Debbugs thread

[Michael Albinus]

Björn Bidar <bjorn.bidar@thaodan.de> writes:

Hi Björn,

>> D'accord. But I guess the subject line quoted here is created by a tool
>> of the guix-patches toolchain. So first we shall agree about the rules
>> of that toolchain (I'm from Emacs, I won't dictate anything!).
>
> The `[PATCH patch-number/patch-count] Subject` subject format is also the
> generate format for Git patch-series. The Guix subject format is a
> variant of this.

So perhaps we check the subject of the message we reply to for

--8<---------------cut here---------------start------------->8---
(rx "[PATCH" (? blank (1+ digit) "/" (1+ digit)) "]")
--8<---------------cut here---------------end--------------->8---

If it matches, we use the subject of the message for the reply, rather
than the title of the bug report.

The regexp should be offered as user option, of course.

Best regards, Michael.