How to change font size only for the buffer *Org Export Dispatcher*?

Question

I'm using emacs with a large font, however I do not need the font to be too large on certain buffers and/or modes. For example, when I use neotree I use a different font and a smaller size, I do that like this:

(add-hook 'neotree-mode-hook '(lambda ()
                              (setq buffer-face-mode-face '(:family "Hack" :height 130 :width semi-condensed))
                              (buffer-face-mode)))

I want to achieve the same thing but for the org export dispatch ui, that is, the buffer that appears when exporting an Org file (by using org-export-dispatch). While this window is active I can not use the describe-mode or see the major-mode so I don't know for which mode I should apply the settings.

I've tried this with no effect:

(defun my-buffer-face-mode-fixed ()
   (interactive)
   (setq buffer-face-mode-face '(:family "Hack" :height 130 :width semi-condensed))
   (buffer-face-mode))

(add-hook 'org-export-before-parsing-hook 'my-buffer-face-mode-fixed)

As well as:

(add-hook 'org-export-stack-mode-hook 'my-buffer-face-mode-fixed)

It doesn't work.

What I was thinking was somehow set the font face for a buffer with a specific name, in that case the question is how to change the font face for the *Org Export Dispatcher* buffer?

While looking about how to change the font on a per name basis I found this on the emacswiki:

 (set-specifier (face-background (get-face 'default)) "blue"
                (get-buffer "*scratch*"))

However the set-specifier function is only available in XEmacs, how can I achieve the same thing in GNU Emacs 26.1?

Answer 1

A glance on org-export--dispatch-ui shows that org-export--dispatch-action is the action right after generating the dispatch buffer. The function org-export--dispatch-action already handles the key-presses for the export options. Therefore you have no other choice than to put the font setting function before org-export--dispatch-action with the help of an advice.

(defcustom org-export-dispatch-buffer-face '(:family "Hack" :height 130 :width semi-condensed)
  "The face specification used by `buffer-face-mode'.
It may contain any value suitable for a `face' text property,
including a face name, a list of face names, a face-attribute
plist, etc."
  :type '(choice (face)
         (repeat :tag "List of faces" face)
         (plist :tag "Face property list"))
  :group 'org-export)

(defun org-export-dispatch-set-font (&rest args)
  "Set font for Org Export Dispatch Buffer."
  (let ((buf (get-buffer "*Org Export Dispatcher*")))
    (when buf
      (with-current-buffer buf
        (apply #'buffer-face-set org-export-dispatch-buffer-face)))))

(advice-add 'org-export--dispatch-action :before #'org-export-dispatch-set-font)

Remark: You could send a feature-request asking for a hook right before org-export--dispatch-action with the Export Dispatch Buffer as current buffer to the org-mode mailing list.