Marcel Taeumel uploaded a new version of Morphic to project The Trunk:
http://source.squeak.org/trunk/Morphic-mt.2004.mcz

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

Name: Morphic-mt.2004
Author: mt
Time: 9 June 2022, 11:22:18.32773 am
UUID: aa7a84f1-7b05-414a-a3e7-107333694eff
Ancestors: Morphic-mt.2003

Fixes regression in prior commit with "fast-window-drag" enabled.

=============== Diff against Morphic-mt.2003 ===============

Item was changed:
  ----- Method: SystemWindow>>mouseEnterDragging: (in category 'events') -----
  mouseEnterDragging: evt
  	"unlock children for drop operations"
  	
  	self flag: #performance. "mt: There may be no need to change appearance if no widget wants the drop. As a trade-off, we avoid expensive visual updates if the user drags a system window and window-embedding in nested world morphs is not allowed."
+ 	(evt hand hasSubmorphs
+ 		and: [evt hand firstSubmorph isSystemWindow]
- 	(evt hand firstSubmorph isSystemWindow
  		and: [Preferences systemWindowEmbedOK not])
  			ifTrue: [^ self].
  
  	self isActive ifTrue: [self lookFocused].
  		
  	(self isActive not and: [evt hand hasSubmorphs]) ifTrue: [
  		self activate. "unlock contents for drop"
  		evt hand addMouseListener: self. "for drop completion on submorph"
  	].!