Drupal node titles are restrictive and do not support italicized text or superscript text (e.g., Book titles, trademark symbols). The HTML Title module allows a limited set of HTML markup (em, sub, sup, b, i, strong, cite, code, bdi, wbr) to be used in node titles. It filters all other markup from titles to prevent XSS vulnerabilities or irrational nesting (e.g., links within links).