Hello,

I've been having a problem recently with gnus hanging when displaying
some messages. Here is a backtrace:

Debugger entered--Lisp error: (quit)
  looking-at("^\\(\\([ 	]*\\(\\w\\|[_.]\\)+>+\\|[ 	]*[]>|]\\)+\\)? *>>>>> +\"\\([^\"\n]+\\)\" +==")
  gnus-cite-parse()
  gnus-cite-parse-wrapper()
  gnus-cite-parse-maybe(nil)
  gnus-article-highlight-citation()
  gnus-treat-article(nil 1 2 "text/html")
  gnus-mime-display-alternative(((#<buffer  *mm*-480880> ("text/plain" (charset . "UTF-8")) quoted-printable nil ("inline") nil nil nil) (#<buffer  *mm*-739229> ("text/html" (charset . "UTF-8")) quoted-printable (lambda nil (let ((inhibit-read-only t)) (delete-region #<marker at 10176 in *Article nnimap+inria:unsorted*> #<marker at 11160 in *Article nnimap+inria:unsorted*>))) nil nil nil nil)) nil nil 1)
  gnus-mime-display-part((#("multipart/alternative" 0 21 (boundary "001a11421902546aae0546297871" buffer #<buffer  *mm*-566770> from "julian.perso@gmail.com" start nil)) (#<buffer  *mm*-480880> ("text/plain" (charset . "UTF-8")) quoted-printable nil ("inline") nil nil nil) (#<buffer  *mm*-739229> ("text/html" (charset . "UTF-8")) quoted-printable (lambda nil (let ((inhibit-read-only t)) (delete-region #<marker at 10176 in *Article nnimap+inria:unsorted*> #<marker at 11160 in *Article nnimap+inria:unsorted*>))) nil nil nil nil)))
  mapcar(gnus-mime-display-part ((#("multipart/alternative" 0 21 (boundary "001a11421902546aae0546297871" buffer #<buffer  *mm*-566770> from "julian.perso@gmail.com" start nil)) (#<buffer  *mm*-480880> ("text/plain" (charset . "UTF-8")) quoted-printable nil ("inline") nil nil nil) (#<buffer  *mm*-739229> ("text/html" (charset . "UTF-8")) quoted-printable (lambda nil (let ((inhibit-read-only t)) (delete-region #<marker at 10176 in *Article nnimap+inria:unsorted*> #<marker at 11160 in *Article nnimap+inria:unsorted*>))) nil nil nil nil)) (#<buffer  *mm*-153958> ("text/plain" (charset . "utf-8")) base64 nil ("inline") nil nil nil)))
  gnus-mime-display-mixed(((#("multipart/alternative" 0 21 (boundary "001a11421902546aae0546297871" buffer #<buffer  *mm*-566770> from "julian.perso@gmail.com" start nil)) (#<buffer  *mm*-480880> ("text/plain" (charset . "UTF-8")) quoted-printable nil ("inline") nil nil nil) (#<buffer  *mm*-739229> ("text/html" (charset . "UTF-8")) quoted-printable (lambda nil (let ((inhibit-read-only t)) (delete-region #<marker at 10176 in *Article nnimap+inria:unsorted*> #<marker at 11160 in *Article nnimap+inria:unsorted*>))) nil nil nil nil)) (#<buffer  *mm*-153958> ("text/plain" (charset . "utf-8")) base64 nil ("inline") nil nil nil)))
  gnus-mime-display-part((#("multipart/mixed" 0 15 (boundary "===============4051021842656490629==" buffer #<buffer  *mm*> from "julian.perso@gmail.com" start nil)) (#("multipart/alternative" 0 21 (boundary "001a11421902546aae0546297871" buffer #<buffer  *mm*-566770> from "julian.perso@gmail.com" start nil)) (#<buffer  *mm*-480880> ("text/plain" (charset . "UTF-8")) quoted-printable nil ("inline") nil nil nil) (#<buffer  *mm*-739229> ("text/html" (charset . "UTF-8")) quoted-printable (lambda nil (let ((inhibit-read-only t)) (delete-region #<marker at 10176 in *Article nnimap+inria:unsorted*> #<marker at 11160 in *Article nnimap+inria:unsorted*>))) nil nil nil nil)) (#<buffer  *mm*-153958> ("text/plain" (charset . "utf-8")) base64 nil ("inline") nil nil nil)))
  gnus-display-mime()
  gnus-article-prepare-display()
  gnus-article-prepare(6137 nil)
  gnus-summary-display-article(6137 nil)
  gnus-summary-select-article(nil nil pseudo)
  gnus-summary-scroll-up(1)
  (if url (progn (browse-url (cdr url)) (gnus-summary-mark-as-read-forward 1)) (gnus-summary-scroll-up arg))
  (let ((url (assq nnrss-url-field (mail-header-extra (gnus-data-header (assq (gnus-summary-article-number) gnus-newsgroup-data)))))) (if url (progn (browse-url (cdr url)) (gnus-summary-mark-as-read-forward 1)) (gnus-summary-scroll-up arg)))
  spacemacs/browse-nnrss-url(1)
  funcall-interactively(spacemacs/browse-nnrss-url 1)
  call-interactively(spacemacs/browse-nnrss-url nil nil)
  command-execute(spacemacs/browse-nnrss-url)

Has someone encountered such a problem? (Google did not help me, except
for a 15 years old message
http://ding.gnus.narkive.com/OdAmfVRg/gnus-hangs-on-articles where
message-cite-prefix-regexp was customized, which I did not do).

Thanks,

Alan

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