diff --git a/collects/drscheme/private/debug.ss b/collects/drscheme/private/debug.ss
index 52b129429c..8deb7ba257 100644
--- a/collects/drscheme/private/debug.ss
+++ b/collects/drscheme/private/debug.ss
@@ -254,7 +254,7 @@ profile todo:
                 (write-special note (current-error-port))
                 (display #\space (current-error-port)))))))
       
-      (define (show-error-and-highlight msg exn highlight-errors)
+    (define (show-error-and-highlight msg exn highlight-errors)
         (let ([cms
                (and (exn? exn) 
                     (continuation-mark-set? (exn-continuation-marks exn))
diff --git a/collects/drscheme/private/rep.ss b/collects/drscheme/private/rep.ss
index 5f12636586..053a337784 100644
--- a/collects/drscheme/private/rep.ss
+++ b/collects/drscheme/private/rep.ss
@@ -232,9 +232,7 @@ TODO
               (parameterize ([current-eventspace drscheme:init:system-eventspace])
                 (queue-callback
                  (λ ()
-                   (send rep highlight-errors
-                         src-locs 
-                         (filter (λ (x) (is-a? (car x) text%)) stack)))))))))
+                   (send rep highlight-errors src-locs stack))))))))
       
       (define (main-user-eventspace-thread?)
         (let ([rep (current-rep)])
@@ -754,7 +752,10 @@ TODO
           ;;                       (union #f (listof (list (is-a?/c text:basic<%>) number number)))
           ;;                    -> (void)
           (define/public (highlight-errors raw-locs error-arrows)
-            (let ([locs (filter (λ (loc) (and (is-a? (srcloc-source loc) text:basic<%>)
+            (let ([locs (filter (λ (loc) (and (or (is-a? (srcloc-source loc) text:basic<%>)
+                                                  (and (path? (srcloc-source loc))
+                                                       (equal? (normalize-path (srcloc-source loc))
+                                                               (send (get-definitions-text) get-filename))))
                                               (number? (srcloc-position loc))
                                               (number? (srcloc-span loc))))
                                 raw-locs)])
@@ -762,7 +763,12 @@ TODO
               
               (set! error-ranges locs)
               
-              (for-each (λ (loc) (send (srcloc-source loc) begin-edit-sequence)) locs)
+              (for-each (λ (loc) 
+                          (let ([ed (if (path? (srcloc-source loc))
+                                        (get-definitions-text)
+                                        (srcloc-source loc))])
+                            (send ed begin-edit-sequence)))
+                        locs)
               
               (when color?
                 (let ([resets
@@ -802,7 +808,11 @@ TODO
                       (send first-file set-position first-start first-start))
                     (send first-file scroll-to-position first-start #f first-finish)))
                 
-                (for-each (λ (loc) (send (srcloc-source loc) end-edit-sequence)) locs)
+                (λ (loc) 
+                          (let ([ed (if (path? (srcloc-source loc))
+                                        (get-definitions-text)
+                                        (srcloc-source loc))])
+                            (send ed end-edit-sequence)))
                 
                 (when first-loc
                   (send first-file set-caret-owner (get-focus-snip) 'global)))))
diff --git a/collects/drscheme/private/unit.ss b/collects/drscheme/private/unit.ss
index 97933c2eb7..6b99a876d4 100644
--- a/collects/drscheme/private/unit.ss
+++ b/collects/drscheme/private/unit.ss
@@ -3456,14 +3456,15 @@ module browser threading seems wrong.
             (compute-new-string))
           (let ([dc (get-dc)])
             (send dc set-font small-control-font)
-            (let-values ([(w h) (get-client-size)])
+            (let*-values ([(tw th _1 _2) (send dc get-text-extent to-draw-message)]
+                          [(w h) (values (+ tw (get-left-side-padding)) th)])
               (send dc set-pen (get-panel-background) 1 'transparent)
               (send dc set-brush (get-panel-background) 'transparent)
               (send dc draw-rectangle 0 0 w h)
               (when yellow?
                 (send dc set-pen "black" 1 'transparent)
                 (send dc set-brush "yellow" 'solid)
-                (send dc draw-rectangle (get-left-side-padding) 0 (- w (get-left-side-padding)) h))
+                (send dc draw-rectangle (get-left-side-padding) 0 tw th))
               (send dc draw-text to-draw-message (get-left-side-padding) 0))))
         
         (super-new [style '(transparent)])
@@ -3473,7 +3474,7 @@ module browser threading seems wrong.
         
         (inherit min-height)
         (let ([dc (get-dc)])
-          (let-values ([(w2 h2 _3 _4) (send dc get-text-extent message small-control-font)])
+          (let-values ([(w2 h2 _3 _4) (send dc get-text-extent "x" small-control-font)])
             (min-height (inexact->exact (floor h2)))))))
     
     (define language-label-message%