[Pharo-users] were Changesets at one point zipped?

Hi guys were Changesets at one point zipped? Else I do not understand the reference to GZipReadStream Stef ChangeSet class>>fileIntoNewChangeSet: fullName "File in all of the contents of the currently selected file, if any, into a new change set." | fn ff | fullName ifNil: [^ Beeper beep]. fn := (Smalltalk hasClassNamed: #GZipReadStream) ifTrue: [(Smalltalk classNamed: #GZipReadStream) uncompressedFileName: fullName] ifFalse: [fullName]. [ ff := FileStream readOnlyFileNamed: fn. self newChangesFromStream: ff named: (FileDirectory localNameFor: fn)] ensure: [ff ifNotNil: [ff close]]