🚀 go-pugleaf

I suggest somethink like the following is added to GNUS.  It replaces
attempted use of overstriking to create underline and bold text with
text properties. For example:

	_t_e_x_t

is displayed as `text' with underline face and

	tteexxtt

is displayed as `text' in bold face.

This is common in some newsgroups.  I don't think the code gives a
measurable delay for articles that does not use overstriking, a single
call to `search-forward' for the backspace.

(defun gnus-article-prepare-overstrike ()
  ;; Prepare article for overstrike commands.
  (save-excursion
    (set-buffer gnus-article-buffer)
    (let ((buffer-read-only nil))
      (while (search-forward "\b" nil t)
	(let ((next (following-char))
	      (previous (char-after (- (point) 2))))
	  (cond ((eq next previous)
		 (delete-region (- (point) 2) (point))
		 (put-text-property (point) (1+ (point))
				    'face 'bold))
		((eq next ?_)
		 (delete-region (1- (point)) (1+ (point)))
		 (put-text-property (1- (point)) (point)
				    'face 'underline))
		((eq previous ?_)
		 (delete-region (- (point) 2) (point))
		 (put-text-property (point) (1+ (point))
				    'face 'underline))))))))

(add-hook 'gnus-article-prepare-hook 'gnus-article-prepare-overstrike)