emacs-29 3204825f560: Fix mangled Subject header field when forwarding (Bug#67360)

[Bill Wohler]

branch: emacs-29
commit 3204825f56040df0a783de4fc99052eabb62b84b
Author: Mike Kupfer <kupfer@rawbw.com>
Commit: Bill Wohler <wohler@newt.com>

    Fix mangled Subject header field when forwarding (Bug#67360)
    
    * lisp/mh-e/mh-comp.el (mh-forward): Overwrite subject when
    forwarding.
---
 lisp/mh-e/mh-comp.el | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lisp/mh-e/mh-comp.el b/lisp/mh-e/mh-comp.el
index 92d31bf1826..0d1dcdf626a 100644
--- a/lisp/mh-e/mh-comp.el
+++ b/lisp/mh-e/mh-comp.el
@@ -574,7 +574,7 @@ See also `mh-compose-forward-as-mime-flag',
         (setq orig-subject (mh-get-header-field "Subject:")))
       (let ((forw-subject
              (mh-forwarded-letter-subject orig-from orig-subject)))
-        (mh-insert-fields "Subject:" forw-subject)
+        (mh-modify-header-field "Subject" forw-subject t)
         (goto-char (point-min))
         ;; Set the local value of mh-mail-header-separator according to what is
         ;; present in the buffer...