..

original commit: 9c267610a5adcf4dca194ae82895f0bfb0e3c4c9

collects/framework/private/group.ss

@@ -134,7 +134,7 @@
                    (quicksort
                     (get-frames)
                     (lambda (x y) (string-ci<=? (send x get-label) (send y get-label))))])
-              (let loop ([windows sorted]
+              (let loop ([windows (filter (lambda (x) (send x is-shown?)) sorted)]
                          [prev (car (last-pair sorted))])
                 (cond
                   [(null? windows) (void)]

collects/framework/private/main.ss

@@ -86,6 +86,7 @@
 	(for-each (lambda (x) 
 		    (hash-table-put! hash-table x 'lambda))
 		  '(
+		    cases
                     instantiate super-instantiate
                     lambda let let* letrec recur
 		    match-lambda match-lambda*