Remove custom theme configuration

README.org

@@ -201,7 +201,6 @@ the ~custom-file~ as [[info:emacs#Saving Customizations][saving customizations (
        htmlize                    ; convert buffer contents to HTML
        iedit                      ; simultaneous multi-entity editing
        laas                       ; LaTeX Auto-Activating Snippets
-       leuven-theme               ; beautiful color theme
        magit                      ; Git Text-based User Interface
        marginalia                 ; minibuffer margin notes
        markdown-mode              ; markdown text mode
@@ -2193,6 +2192,9 @@ code formatter for Python]].
 :CUSTOM_ID: sec:appearance
 :END:
 
+This setup does not configure [[info:emacs#Custom Themes][custom themes (info)]] in order to prevent endless
+useless tweaking.
+
 ** [[info:emacs#Faces][Text faces (or styles)]]
 :PROPERTIES:
 :CUSTOM_ID: sec:text-faces-or-styles
@@ -2289,60 +2291,6 @@ and names in buffers for debugging.
     (rainbow-mode +1))
 #+end_src
 
-** [[info:emacs#Custom Themes][Custom Themes (info)]]
-:PROPERTIES:
-:CUSTOM_ID: sec:custom-themes
-:END:
-
-This setup prefers the ~leuven~ and ~leuven-dark~ themes because the
-~modus-operandi~ and ~modus-vivendi~ themes feel quirky: for instance those
-themes fail to display ~hl-line-mode~ properly with Emacs-27.2 on Darwin.
-
-[[https://emacs.stackexchange.com/questions/17431/how-do-i-change-portions-of-a-custom-theme][How to change custom theme faces]]
-
-#+caption[Hack =leuven-theme=]:
-#+caption: Hack =leuven-theme=.
-#+name: lst:hack-leuven-theme
-#+begin_src emacs-lisp
-  (unless noninteractive
-    ;; Try to detect `leuven-theme` from MELPA.
-    (when (fboundp 'leuven-scale-font)
-      (custom-set-variables
-       '(leuven-scale-org-agenda-structure 1.0)
-       '(leuven-scale-org-document-title 1.0)
-       '(leuven-scale-outline-headlines 1.0)
-       '(leuven-scale-volatile-highlight 1.0)))
-
-    (defun my-leuven-hook-function ()
-      (when (member 'leuven custom-enabled-themes)
-        (let ((custom-inhibit--theme-enable nil)
-              (ol1 (list :height 1.0 :weight 'bold
-                         :foreground "#3C3C3C" :background "#F0F0F0"))
-              (ol2 (list :height 1.0 :weight 'bold
-                         :foreground "#123555" :background "#E5F4FB")))
-          (custom-theme-set-faces
-           'leuven
-           `(font-latex-sectioning-2-face ((t ,ol1)))
-           `(font-latex-sectioning-3-face ((t ,ol2)))
-           `(info-title-1 ((t ,ol1)))
-           `(markdown-header-face-1 ((t ,ol1)))
-           `(markdown-header-face-2 ((t ,ol2)))
-           `(org-level-1 ((t ,ol1)))
-           `(org-level-2 ((t ,ol2)))
-           `(outline-1 ((t ,ol1)))
-           `(outline-2 ((t ,ol1)))))
-        (enable-theme 'leuven)))
-
-    ;; (load-theme 'leuven 'no-confirm nil)
-
-    (dolist (hook '(Info-mode-hook
-                    LaTeX-mode-hook
-                    markdown-mode-hook
-                    org-mode-hook
-                    outline-mode-hook))
-      (add-hook hook #'my-leuven-hook-function)))
-#+end_src
-
 ** [[https://karthinks.com/software/batteries-included-with-emacs/][Flash the line around point for visual feedback]]
 :PROPERTIES:
 :CUSTOM_ID: sec:flash-line-around-point