Tim Felgentreff uploaded a new version of Kernel to project The Trunk:
http://source.squeak.org/trunk/Kernel-tfel.1039.mcz

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

Name: Kernel-tfel.1039
Author: tfel
Time: 23 September 2016, 1:49:11.864418 pm
UUID: 9e2d7733-0e85-1140-b333-5725f60a8877
Ancestors: Kernel-bf.1038

- hide uniclasses from the environment, so they are collected automatically when their players go away. One can always browse such classes using the InstanceBrowser, anyway.

=============== Diff against Kernel-bf.1038 ===============

Item was changed:
  ----- Method: Object class>>newUniqueClassInstVars:classInstVars: (in category 'instance creation') -----
  newUniqueClassInstVars: instVarString classInstVars: classInstVarString
  	"Create a unique class for the receiver"
  
  	| aName aClass |
  	self isSystemDefined ifFalse:
  		[^ superclass newUniqueClassInstVars: instVarString classInstVars: classInstVarString].
  	aName := self chooseUniqueClassName.
  	aClass := self subclass: aName instanceVariableNames: instVarString 
  		classVariableNames: '' poolDictionaries: '' category: self categoryForUniclasses.
+ 	self flag: #todo. self flag: #uniclasses. "Discuss if we really want to hide uniclasses again"
+ 	aClass environment forgetClass: aClass logged: false.
+ 	self removeSubclass: aClass.
  	classInstVarString size > 0 ifTrue:
  		[aClass class instanceVariableNames: classInstVarString].
  	^ aClass!