The attached changeset prevents this by rounding boundary values, although i don't know if it is the best way to do it. maybe it would be better to make a special extent: method in FlapTab or to deal with this in a completely different way...
Layoutchanged method in flaptab sends an extent: message again and because of the failing condition it runs in an infinite loop.

I think this phenomenon is the same that Jim Benson reported almost a
year ago ([BUG] setFlapsFontTo: 32 bit display (9 April 2003), but he
suspected a different cause.

Alex

extent: aPoint
	bounds extent = aPoint ifTrue: [^ self].
	self changed.
	bounds _ bounds topLeft extent: aPoint.
	self layoutChanged.
	self changed.


from preamble:

"Change Set:		RoundedMorphBounds
Date:			25 March 2004
Author:			Alexander at Lazarevic.de

Prevents an infinite loop in some cases when FlapTab Morphs have floats
in their boundry"!
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