Christoph Thiede uploaded a new version of System to project The Trunk:
http://source.squeak.org/trunk/System-ct.1252.mcz

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

Name: System-ct.1252
Author: ct
Time: 22 November 2021, 6:47:47.026308 pm
UUID: 41cfb410-42cc-e44b-9c2d-9650f6c85866
Ancestors: System-ct.1251

Cleans up Preferences class >> #categoryList. The unclassified category has no special semantics when editing or accessing preferences. It is only added to every preference with zero categories by default. If there is any unclassified category, it will already contain #unclassified in its category list.

=============== Diff against System-ct.1251 ===============

Item was changed:
  ----- Method: Preferences class>>categoryList (in category 'support') -----
  categoryList
  	"Return all available categories. No duplicates."
  
  	| aSet |
  	aSet := Set new.
  	self allPreferences do: [ :aPreference | 
  		aSet addAll: (
  			aPreference categoryList collect: [ :aCategory |
  				aCategory asSymbol ]) ].
- 	
- 	aSet add: self unclassifiedCategory.
- 	
  	^aSet!