There seems to be a slight performance problem with this method:

readOnlyFileNamed: fileName 
	"Open an existing file with the given name for reading."
	"Changed to open a more usefull popup menu.  It now also includes
the most likely choices.  jaf"
	| selection dir files choices newName fullName |
	fullName _ self fullName: fileName.
	(self isAFileNamed: fullName)
		ifTrue: [^ self new open: fullName forWrite: false].
	...

And now look at:
isAFileNamed: fileName
	"Answer true if a file of the given name exists."

	| f |
	f _ self new open: fileName forWrite: false.
	f ifNil: [^ false].
	f close.
	^ true

Note that there is two new open:forWrite: calls to open a single file.  If
we change the previous code to:

readOnlyFileNamed: fileName 
	"Open an existing file with the given name for reading."
	"Changed to open a more usefull popup menu.  It now also includes
the most likely choices.  jaf"
	| selection dir files choices newName fullName |
	fullName _ self fullName: fileName.
	f := self new self new open: fullName forWrite: false.
	f isNil ifFalse: [^f].
	...

Would this not be more efficient ?  It looks like the latest release could
use this same trick.

Does anybody see anything wrong with submitting this change as an [enh] ?