From bef4dbc067e2bb735920d9c5026fea35e25e92c6 Mon Sep 17 00:00:00 2001
From: Kris Maglione <maglione.k@gmail.com>
Date: Mon, 14 Mar 2011 13:59:53 -0400
Subject: [PATCH] Closes issue #443.

---
 common/content/events.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/common/content/events.js b/common/content/events.js
index f962fe81..d3fd363f 100644
--- a/common/content/events.js
+++ b/common/content/events.js
@@ -1482,8 +1482,11 @@ var Events = Module("events", {
     isHidden: function isHidden(elem, aggressive) {
         for (let e = elem; e instanceof Element; e = e.parentNode) {
             if (util.computedStyle(e).visibility !== "visible" ||
-                    aggressive && e.boxObject && e.boxObject.height === 0)
+                    aggressive && !/set$/.test(e.localName)
+                        && e.boxObject && e.boxObject.height === 0)
                 return true;
+            else if (e.namespaceURI == XUL && e.localName === "panel")
+                break;
         }
         return false;
     },