Guillermo Polito and Benjamin Van Ryseghem, Could you check your changes made to ProtocolBrowser>>initListFrom: selectorCollection highlighting: aClass ? It's related to http://code.google.com/p/pharo/issues/detail?id=3088 Basically, Guillermo added the line stringVersion: item asString and then Benjamin replaced it with stringVersion: item So, now the Protocol Browser is creating SourceMethodReferences with Texts as stringVersion. you can view those instances if you follow the steps and then execute SourcedMethodReference allInstances select: [:each | each stringVersion class == Text ] And it leads to http://code.google.com/p/pharo/issues/detail?id=3088 For what i saw, the fix will be to add Guillermo's line again but im not sure. its confusing. What do you think? Thanks