In PHPRunner 8.1 this is the way it works, you can use any HTML tags in field labels.
HJB12/16/2015
http://www.xlinesoft.com/tutorials/VisualEditor.htm ... watch the decisive ABRACADABRA scene in the tutorial above when the HYPERLINK setting is showed and see what happened when switching into HTML mode under the VISUAL EDITOR where you can place whatsoever HTML tags in mind.