diff --git a/collects/drracket/private/tooltip.rkt b/collects/drracket/private/tooltip.rkt
index 2dc05e1d06..e188a73216 100644
--- a/collects/drracket/private/tooltip.rkt
+++ b/collects/drracket/private/tooltip.rkt
@@ -69,7 +69,12 @@
     (define/private (update-size)
       (define dc (get-dc))
       (send dc set-font small-control-font)
-      (define-values (w h _1 _2) (send dc get-text-extent (car labels)))
+      (define-values (w h) 
+        (for/fold ([w 0] [h 0])
+                  ([lab (in-list labels)])
+          (define-values (this-w this-h _1 _2) (send dc get-text-extent lab))
+          (values (max this-w w)
+                  (max this-h h))))
       (send (get-parent) begin-container-sequence)
       (min-width (+ 5 (inexact->exact (ceiling w))))
       (min-height (+ 5 (* (length labels) (inexact->exact (ceiling h)))))