diff --git a/browser/components/sessionstore/src/nsSessionStore.js b/browser/components/sessionstore/src/nsSessionStore.js
index 548af239af2c..920895eaaf90 100644
--- a/browser/components/sessionstore/src/nsSessionStore.js
+++ b/browser/components/sessionstore/src/nsSessionStore.js
@@ -2378,8 +2378,15 @@ SessionStoreService.prototype = {
       browser.userTypedValue = activePageData ? activePageData.url || null : null;
 
       // If the page has a title, set it.
-      if (activePageData && activePageData.title)
-        tab.label = activePageData.title;
+      if (activePageData) {
+        if (activePageData.title) {
+          tab.label = activePageData.title;
+          tab.crop = "end";
+        } else if (activePageData.url != "about:blank") {
+          tab.label = activePageData.url;
+          tab.crop = "center";
+        }
+      }
     }
 
     if (!this._isWindowLoaded(aWindow)) {
diff --git a/modules/plugin/test/mochitest/Makefile.in b/modules/plugin/test/mochitest/Makefile.in
index faa6becfe5b3..b6d4b062b0f4 100644
--- a/modules/plugin/test/mochitest/Makefile.in
+++ b/modules/plugin/test/mochitest/Makefile.in
@@ -85,7 +85,6 @@ _MOCHITEST_FILES = \
   neverending.sjs \
   test_newstreamondestroy.html \
   $(warning test_crashing2.html disabled due to random orange; see bug 566049) \
-  test_hanging.html \
   crashing_subpage.html \
   test_GCrace.html \
   test_propertyAndMethod.html \
@@ -122,10 +121,12 @@ endif
 endif
 endif
 
-# Temporarily disable these tests on Mac OS X, see bug 599076 and bug 599267.
+# Temporarily disable these tests on Mac OS X, see bug 599076 and bug 599267
+# and bug 599378.
 ifneq (cocoa,$(MOZ_WIDGET_TOOLKIT))
 _MOCHITEST_FILES += \
   test_crashing.html \
+  test_hanging.html \
   $(NULL)
 
 _MOCHICHROME_FILES += \