Org mode version 9.6.1, GNU Emacs 27.2 (build 1, x86_64-w64-mingw32)

Please see the two screenshots here for illustration:

https://imgur.com/a/7EuUi0J <https://imgur.com/a/7EuUi0J>

(I'm assuming it's not a good idea - or not even possible - to send 
e-mail attachments to the list?)

This is the relevant code from my init.el that seems to be causing this 
issue:

(require 'org-habit nil t) ; relevant?
(defun org-add-my-extra-fonts ()
   "Add alert and overdue fonts."
   (add-to-list 'org-font-lock-extra-keywords 
'("\\(³\\)\\([^\n\r\t]+\\)\\(³\\)" (1 '(face org-habit-alert-face 
invisible nil)) (2 'org-habit-alert-face t) (3 '(face 
org-habit-alert-face invisible nil))) t)
   (add-to-list 'org-font-lock-extra-keywords 
'("\\(§\\)\\([^\n\r\t]+\\)\\(§\\)" (1 '(face org-habit-overdue-face 
invisible nil)) (2 'org-habit-overdue-face t) (3 '(face 
org-habit-overdue-face invisible nil))) t)
   (add-to-list 'org-font-lock-extra-keywords 
'("\\(@\\)\\([^\n\r\t]+\\)\\(@\\)" (1 '(face org-habit-clear-face 
invisible nil)) (2 'org-habit-clear-face t) (3 '(face 
org-habit-clear-face invisible nil))) t))
(add-hook 'org-font-lock-set-keywords-hook #'org-add-my-extra-fonts)

Can you reproduce it?

Thanks!