The *browser control is similar to many of the other PxPlus controls and is resized in the same way.
For non-nomads you have to add the logic yourself to detect a resize event CTL = -1105. Then on that event you can use the [pvx]left, [pvx]top, [pvx]height, and [pvx]width properties of the *browser control to adjust the size and position based on the resize of the window.
The only way for PxPlus to handle it for you is to use Nomads.