TinyMCE Issue: Match url to auto highlight code doesn't seem to work

With pages with TinyMCE, the match url to auto highlight code doesn't seem to work. I can use the context menu to manually set it to highlight the on TinyMCE's code view, but I can't seem to get the automatic highlighting to work. Note, TinyMCE first loads in WYSIWYG mode. Any help would be appreciated.