--- /dev/null
+\version "2.16.0"
+
+\paper {
+ #(include-special-characters)
+}
+
+#(define-markup-list-command (show-special-characters layout props) ()
+ (let ((defs (ly:output-def-lookup layout 'text-font-defaults)))
+ (interpret-markup-list layout props
+ (map (lambda (pair)
+ (markup #:override '(line-width . 18)
+ #:fill-line
+ (#:override '(replacement-alist . ()) (car pair)
+ #:override '(thickness . 0.1) #:box (cdr pair))))
+ (list-tail (assoc-get 'replacement-alist defs) 3)))))
+
+\markuplist \justified-lines \show-special-characters