A new version of Morphic was added to project The Inbox:
http://source.squeak.org/inbox/Morphic-kfr.2002.mcz

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

Name: Morphic-kfr.2002
Author: kfr
Time: 6 June 2022, 11:35:56.143783 am
UUID: 3700dde9-4ef0-c84e-a342-23f649a554e3
Ancestors: Morphic-kfr.2001

Don't activate SystemWindows on drags events it doesn't want

=============== Diff against Morphic-kfr.2001 ===============

Item was changed:
  ----- Method: SystemWindow>>mouseEnterDragging: (in category 'events') -----
  mouseEnterDragging: evt
  	"unlock children for drop operations"
  	
+ 	| textDnD |
  	self flag: #performance. "mt: There may be no need to change appearance if no widget wants the drop."
+ 	
+ 	textDnD := false.
+ 	evt hand hasSubmorphs ifTrue:[textDnD := evt hand firstSubmorph isTransferMorph]. "Workaround: We sometimes get this event triggered when there is no submorph to the hand"
+ 	(textDnD or:[self dropEnabled]) ifFalse: ["if both are false there is no d&d"
+ 		^super mouseEnterDragging: evt].
+ 	
  	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"
  	].!