diff --git a/README.org b/README.org
index 3db0b05..971b538 100644
--- a/README.org
+++ b/README.org
@@ -590,25 +590,18 @@ defined in this Org file.
       ;; Ensure defining the functions before documenting them.
       (define-short-documentation-group init
         "Face"
-        (invert-default-face
-         :no-manual t)
-        (set-default-face-height
-         :no-manual t)
+        (invert-default-face :no-manual t)
+        (set-default-face-height :no-manual t)
         "Org"
-        (org-babel-execute:latex-extra-header
-         :no-manual t)
-        (org-babel-execute:latex-header
-         :no-manual t)
-        (org-electric-dollar
-         :no-manual t)
-        (org-eval-emacs-lisp-setup-blocks
-         :no-manual t)
-        (org-eval-python-setup-blocks
-         :no-manual t)
-        (org-eval-infixed-blocks
-         :no-manual t)
-        (org-syntax-convert-keyword-case-to-lower
-         :no-manual t))))
+        (by-backend :no-manual t)
+        (by-backend-kbd-org-macro :no-manual t)
+        (org-babel-execute:latex-extra-header :no-manual t)
+        (org-babel-execute:latex-header :no-manual t)
+        (org-electric-dollar :no-manual t)
+        (org-eval-emacs-lisp-setup-blocks :no-manual t)
+        (org-eval-python-setup-blocks :no-manual t)
+        (org-eval-infixed-blocks :no-manual t)
+        (org-syntax-convert-keyword-case-to-lower :no-manual t))))
 #+end_src
 
 ** [[info:info#Top][Info (info)]]
@@ -2045,17 +2038,21 @@ Listing [[lst:by-backend-kbd-org-macro]] defines the tools for the definition of
 [[https://orgmode.org/][Org mode]] =kbd= macro on the fifth line of listing
 [[lst:source-file-export-keyword-settings]].
 
+#+attr_latex: :options breaklines
 #+caption[Define the tools of the =Org-mode= =kbd= macro]:
 #+caption: Define the tools for the =Org-mode= =kbd= macro.
 #+name: lst:by-backend-kbd-org-macro
 #+begin_src emacs-lisp
-  (with-eval-after-load 'ox
+  (with-eval-after-load 'emacs
     (autoload 'htmlize-protect-string "htmlize" nil t)
 
+    ;; https://orgmode.org/worg/org-contrib/babel/languages/ob-doc-LaTeX.html#orge5c50fd
     (defmacro by-backend (&rest body)
-      `(cl-case org-export-current-backend ,@body))
+      "Help for org-export backend dependent execution."
+      `(cl-case ',(bound-and-true-p org-export-current-backend) ,@body))
 
     (defun by-backend-kbd-org-macro (keys)
+      "Help for an org-export backend dependent \"#+macro: kbd\"."
       (by-backend
        (html (format "@@html:<kbd>%s</kbd>@@" (htmlize-protect-string keys)))
        (latex (format "@@latex:\\colorbox{PowderBlue}{\\texttt{%s}}@@" keys)))))