"sa-learn --forget msg" gives the following warning

message: _normalize() was given characters, expected bytes: darkThemeSupport=true backgroundImageSupport=true headerImage

on the message (which I've reduced to the following lines):

Content-Transfer-Encoding: quoted-printable
Content-Type: text/html; charset="UTF-8"
MIME-Version: 1.0

pener"> D=C3=A9couvrir d'autres =C3=A9v=C3=A9nements </a></td></tr></table>=
</tr></table><![endif]--></td></tr></tbody></table></div><script type=3D"te=
xt/plain">darkThemeSupport=3Dtrue backgroundImageSupport=3Dtrue headerImage=

I've also reported the bug upstream.

Note: the --forget is just an example; it also occurs with --spam.

This is annoying since I run sa-learn via cron, and I get spammed
each time it is run. However, I could remove the culprit message
(which I identified with the -D option).

Control: severity -1 important
Control: tags -1 upstream fixed-upstream

The message is actually not new, so this appears to be a regression
in 4.0.2+svn1938422-1 (22 Sep 2026). Upstream says that r1938519
probably fixes it, and I confirm that r1938519 makes the issue
disappear.

We believe that the bug you reported is fixed in the latest version of
spamassassin, which is due to be installed in the Debian FTP archive.

A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 1148999@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Noah Meyerhans <noahm@debian.org> (supplier of updated spamassassin package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@ftp-master.debian.org)
Format: 1.8
Date: Wed, 14 Oct 2026 17:12:57 -0400
Source: spamassassin
Architecture: source
Version: 4.0.2+svn1939112-1
Distribution: unstable
Urgency: medium
Maintainer: Noah Meyerhans <noahm@debian.org>
Changed-By: Noah Meyerhans <noahm@debian.org>
Closes: 1148999
Changes:
 spamassassin (4.0.2+svn1939112-1) unstable; urgency=medium
 .
   * New upstream snapshot (Closes: #1148999)
   * Fix upstream perlcritic issues
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 1060a4211de2284fe04c1adbe808bfc592f1a822 49740 spamassassin_4.0.2+svn1939112-1.debian.tar.xz
 26dcf7dd20a78dec7b1bf5b16b0f31a269655dbd 8786 spamassassin_4.0.2+svn1939112-1_source.buildinfo
Checksums-Sha256:
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Files:
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