A new version of Protocols was added to project The Inbox:
http://source.squeak.org/inbox/Protocols-jr.67.mcz

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

Name: Protocols-jr.67
Author: jr
Time: 10 August 2019, 11:17:13.691208 pm
UUID: 47e86587-b8a1-6341-b25f-624fe55eb0e4
Ancestors: Protocols-jr.66

Harden against missing methods.

Endless debuggers appeared when a message list item whose method was removed from the system was hovered. This can happen if you have an existing message list that was not updated since the method has been removed.

=============== Diff against Protocols-jr.66 ===============

Item was changed:
  ----- Method: Lexicon>>messageHelpAt: (in category 'message list') -----
  messageHelpAt: anIndex
  	"Show the first n lines of the source code of the selected message."
  	Preferences balloonHelpInMessageLists ifFalse: [^ nil].
  	self messageList size < anIndex ifTrue: [^ nil].
  	
  	self class parse: (self messageList at: anIndex) toClassAndSelector:
  		[:class :selector |
+ 		^ self messageHelpForMethod: (class compiledMethodAt: selector ifAbsent: [^ nil])].
- 		^ self messageHelpForMethod: class >> selector].
  	
  	^ nil!