tim Rowledge uploaded a new version of Nebraska to project The Trunk:
http://source.squeak.org/trunk/Nebraska-tpr.57.mcz

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

Name: Nebraska-tpr.57
Author: tpr
Time: 10 May 2020, 6:23:13.835738 pm
UUID: 52d8a16e-0096-4d51-a380-0fe4b0732434
Ancestors: Nebraska-mt.56

Correct a case of assigning to a block arg

=============== Diff against Nebraska-mt.56 ===============

Item was changed:
  ----- Method: NebraskaSenderMorph>>hideField: (in category 'as yet unclassified') -----
  hideField: aFieldName
+ 	fields at: aFieldName ifPresent: [:f| |m |
+ 		m := f.
- 	fields at: aFieldName ifPresent: [:m |
  		[m owner notNil and: [m owner submorphs size =1]]
  			whileTrue: [m := m owner].
  		m delete]!