Andreas Raab uploaded a new version of Morphic to project The Trunk:
http://source.squeak.org/trunk/Morphic-kb.316.mcz

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

Name: Morphic-kb.316
Author: kb
Time: 2 February 2010, 4:03:01.299 pm
UUID: d07a5832-b019-af42-a895-6657f8cea43a
Ancestors: Morphic-dtl.315

 - fix for: http://bugs.squeak.org/view.php?id=7462

The fix adds a check to SystemWindow >> activate, to avoid sending #addPaneSplitters if the window isCollapsed. 

=============== Diff against Morphic-dtl.315 ===============

Item was changed:
  ----- Method: SystemWindow>>activate (in category 'top window') -----
  activate
  	"Activate the owner too."
  
  	|mo mc|
  	mo := self modalOwner.
  	mc := self modalChild.
  	mc isNil
  		ifFalse: [mc owner notNil ifTrue: [
  				mc activate.
  				^mc modalChild isNil ifTrue: [mc flash]]].
+ 	(isCollapsed not and: [ 
+ 		self paneMorphs size > 1 and: [ 
+ 			self splitters isEmpty ] ]) ifTrue: [ self addPaneSplitters ].
- 	(self paneMorphs size > 1 and: [self splitters isEmpty])
- 		ifTrue: [self addPaneSplitters].
  	self activateWindow.
  	self rememberedKeyboardFocus
  		ifNil: [(self respondsTo: #navigateFocusForward)
  				ifTrue: [self navigateFocusForward]]
  		ifNotNil: [:m | m world
  						ifNil: [self rememberKeyboardFocus: nil] "deleted"
  						ifNotNil: [:w | 
  							m wantsKeyboardFocus
  								ifTrue: [m takeKeyboardFocus]
  								ifFalse: [(self respondsTo: #navigateFocusForward)
  											ifTrue: [self navigateFocusForward]]]].
  	(mo notNil and: [mo isKindOf: SystemWindow])
  		ifTrue: [mo bringBehind: self]!