Tim Felgentreff uploaded a new version of MorphicExtras to project The Trunk:
http://source.squeak.org/trunk/MorphicExtras-tfel.178.mcz

==================== Summary ====================

Name: MorphicExtras-tfel.178
Author: tfel
Time: 28 July 2016, 5:40:57.037262 pm
UUID: 7f1a4b18-8035-ab4c-a0e6-f61404b53cd9
Ancestors: MorphicExtras-mt.177

use a default value for flaptabs if we don't have a referent

=============== Diff against MorphicExtras-mt.177 ===============

Item was changed:
  ----- Method: FlapTab>>referentThickness (in category 'access') -----
  referentThickness
+ 	referent ifNil: [^ 32].
  	^ (self orientation == #horizontal)
  		ifTrue:
  			[referent height]
  		ifFalse:
  			[referent width]!