I've got both changesets loaded (in an otherwise vanilla image AFAICT),
and the ObjectExplorer blows up on a yellow-button click when no tree
element is selected, with the following error:

VM: unix - Squeak3.4 of 1 March 2003 [latest update: #5170]
Image: Squeak3.6beta [latest update: #5373]

SmallInteger(Object)>>doesNotUnderstand: #parent
	Receiver: 1
	Arguments and temporary variables: 
		aMessage: 	a Message with selector: #parent and arguments: #()
	Receiver's instance variables: 
1

ObjectExplorer>>parentObject
	Receiver: an ObjectExplorer
	Arguments and temporary variables: 

	Receiver's instance variables: 
		dependents: 	#(a SystemWindow(1828) a SimpleHierarchicalListMorph(526)
a Pluggab...etc...
		currentSelection: 	1
		myBrowser: 	nil
		rootObject: 	a BugFixArchiveViewer(3753)
		inspector: 	nil
		monitorList: 	nil

ObjectExplorer>>genericMenu:
	Receiver: an ObjectExplorer
	Arguments and temporary variables: 
		aMenu: 	a MenuMorph(1083)
		insideObject: 	1
		menu: 	nil
		parentObject: 	nil
		i: 	nil
	Receiver's instance variables: 
		dependents: 	#(a SystemWindow(1828) a SimpleHierarchicalListMorph(526)
a Pluggab...etc...
		currentSelection: 	1
		myBrowser: 	nil
		rootObject: 	a BugFixArchiveViewer(3753)
		inspector: 	nil
		monitorList: 	nil

















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