One problem I found after uninstalling my extension function is with #+BEGIN/END blocks. For example, enable fontification for python, elisp or whatever and write a long block like this:
#+BEGIN_XXX python def xxx(x): pass def xxx(x): pass ... #+END_XXX python Now scroll down to the end and change python to pyton and back. Even when the delimiter is restored fontification isn't. I see that, for latex blocks, you have added a case for searching backwards for an opening delimiter. But org-fontify-meta-lines-and-blocks-1 lacks a similar logic.
