At one time, PB had a WEB Target feature that allowed the PB developer to edit HTML web pages right inside the IDE. However, Sybase removed that feature a long time ago.
FWIW: I use the open source product known as KompoZer for editing my HTML web pages. You can even create a short-cut in the PB IDE (custom toolbar item) to launch KompoZer (or another equivalent product) to make HTML editing in your web project more convenient.
Regards ... Chris