diff --git a/mozilla/widget/src/cocoa/nsCocoaWindow.mm b/mozilla/widget/src/cocoa/nsCocoaWindow.mm
index 704d23b6345..2909203aab0 100644
--- a/mozilla/widget/src/cocoa/nsCocoaWindow.mm
+++ b/mozilla/widget/src/cocoa/nsCocoaWindow.mm
@@ -2159,7 +2159,10 @@ already_AddRefed<nsIDOMElement> GetFocusedElement()
 // NSWindow's own sendEvent: method.
 - (void)nsCocoaWindow_NSWindow_sendEvent:(NSEvent *)anEvent
 {
-  NS_OBJC_BEGIN_TRY_ABORT_BLOCK;
+  // Since we've hooked a "system call" ([NSWindow sendEvent:]), we're always
+  // called from system code (not browser code).  So avoid crashing on any
+  // Objective-C exceptions that occur here.
+  NS_OBJC_BEGIN_TRY_LOGONLY_BLOCK;
 
   nsCOMPtr<nsIDOMElement> oldFocusedElement;
   NSResponder *oldFirstResponder;
@@ -2198,7 +2201,7 @@ already_AddRefed<nsIDOMElement> GetFocusedElement()
     [oldFirstResponder release];
   }
 
-  NS_OBJC_END_TRY_ABORT_BLOCK;
+  NS_OBJC_END_TRY_LOGONLY_BLOCK;
 }
 
 @end
diff --git a/mozilla/xpcom/base/nsObjCExceptions.h b/mozilla/xpcom/base/nsObjCExceptions.h
index d7be453aa93..40af53fe5fc 100644
--- a/mozilla/xpcom/base/nsObjCExceptions.h
+++ b/mozilla/xpcom/base/nsObjCExceptions.h
@@ -221,4 +221,9 @@ NS_OBJC_TRY(_e, )
                                                 }                               \
                                                 return _rv;
 
+#define NS_OBJC_BEGIN_TRY_LOGONLY_BLOCK @try {
+#define NS_OBJC_END_TRY_LOGONLY_BLOCK   } @catch(NSException *_exn) {           \
+                                          nsObjCExceptionLog(_exn);             \
+                                        }
+
 #endif // nsObjCExceptions_h_