Hi, I am trying to use org-src.el bundled in org-mode to support syntax highlighgint for multiple languages in my IPython notebook client in Emacs (EIN) [1]. It works very well but I need to patch (please see the attached file) it to use. The problem is that fontification is gone when I edit the buffer. I found that I can workaround this problem by putting font-lock-face property instead of face property. When the fontification vanishes, (text-properties-at (point)) returns (font-lock-fontified t fontified t) Before the fontification vanishes (before inserting a cell), (text-properties-at (point)) returns this at the same point: (font-lock-multiline t face font-lock-keyword-face font-lock-fontified t fontified t) I couldn't reproduce this problem outside of EIN (in org-mode or other plain buffers). I am thinking about including my version of org-src-font-lock-fontify-block in EIN, but Dan Davison suggested to ask in this ML because it could be a problem in org-mode too. Does anyone know what is happening here? Could this happen in org-mode too? See [2] for the original discussion. [1] https://github.com/tkf/emacs-ipython-notebook/ [2] https://github.com/tkf/emacs-ipython-notebook/issues/2