A new HTML editor will replace the current richtext editor, and some strings have changed in the English translation (lang/en/moodle.php) to become more generic:
$string['helprichtext'] = "About the HTML editor";
$string['htmleditor'] = "Use HTML editor (some browsers only)";
$string['htmleditoravailable'] = "The HTML editor is available";
$string['htmleditordisabled'] = "You have disabled the HTML editor in your user profile";
$string['htmleditordisabledadmin'] = "The administrator has disabled the HTML editor on this site";
$string['htmleditordisabledbrowser'] = "The HTML editor is unavailable because your web browser is not compatible";
.