OK, I'm done with the preg_replace() in the paragraph parser. It's too buggy. Replaced with preg_match_all()/str_replace_once().
/*
* Auto-completing page/username fields
* NOTE: A more efficient version of the username field is used for Mozilla browsers. The updated code is in autofill.js.
*/
//
// **** 1.1.5: DEPRECATED ****
// Replaced with jQuery-based mechanism.
//