See the regexp at https://git.savannah.gnu.org/cgit/emacs/org-mode.git/tree/lisp/org-element.el?h=d1e4b9351941aa9241ab3aa0a34256376b7eca94#n2420.
See the regexp at https://git.savannah.gnu.org/cgit/emacs/org-mode.git/tree/lisp/org-element.el?h=d1e4b9351941aa9241ab3aa0a34256376b7eca94#n2420.