Button labels in MVC windows have their labels centered as though the 
window had no border.  If the window does have a border of moderate 
thickness, a button appearing near the outside of the window will 
have its label misaligned, in some cases invisible.

(The bug is not apparent in the stock browser windows because their 
StandardSystemView windows have thin borders and the buttons are not 
near the outside of the window.  For buttons resting entirely 
"inside" the border, the centering is unaffected by the bug)

I have not tested to whether there is an analogous bug in Morphic.

The following code is not really a fix -- it is flawed in that it 
introduces a magic number and recomputes the centering each time the 
window is displayed, but it may perhaps help to illustrate a solution 
to this problem that leaves existing windows unaffected.  I leave it 
to folks with a better understanding of the code to address the 
problem (The computation in centerLabel, via getWindow, appearing 
essentially centering the label bounding box in itself, left me 
baffled, so I left it alone).

PluggableButtonView>>displayView

	"Displays this switch and its label, if any."

	self clearInside.
	label ifNotNil: [
		(label isKindOf: Paragraph) ifTrue: [
			label foregroundColor: self foregroundColor
				 backgroundColor: self backgroundColor].
		label
			align: (label boundingBox center + (0 at 2))
			with: self insetDisplayBox center.
		label displayOn: Display
				at: label boundingBox topLeft
				clippingBox: self insetDisplayBox].
	complemented _ false.