Teemu Likonen <tlikonen@iki.fi> writes:

> I've been using Emacs 25.0.92 for a while and noticed that Gnus has
> started to display attached pdf files with doc-view-mode (inside Emacs)
> instead of launching an external viewer. In mailcap-mime-data variable I
> have external viewer (Okular) first for the application/pdf MIME type
> but Gnus doesn't want to respect that.

This is not a Gnus problem, but Emacs have changed to default to
docview-mode for pdf files, ignoring mailcap.

> How do configure Gnus to use external viewer for attached pdf files?

;;Remove doc-view so pdf will open with ocular
(setcdr
   (assoc "application" mailcap-mime-data)
   (remove '("pdf"
             (viewer . doc-view-mode)
             (type . "application/pdf")
             (test eq window-system 'x))
           (cdr (assoc "application" mailcap-mime-data))))

Charles

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