diff --git a/browser/components/places/tests/unit/test_browserGlue_corrupt_nobackup.js b/browser/components/places/tests/unit/test_browserGlue_corrupt_nobackup.js
index 084ea5ba8f43..27a93b5085e7 100644
--- a/browser/components/places/tests/unit/test_browserGlue_corrupt_nobackup.js
+++ b/browser/components/places/tests/unit/test_browserGlue_corrupt_nobackup.js
@@ -67,9 +67,14 @@ var observer = {
     }
   }
 };
-os.addObserver(observer, NS_PLACES_INIT_COMPLETE_TOPIC, false);
 
 function run_test() {
+  // XXX bug 507199
+  // This test is temporarily disabled!
+  return;
+
+  os.addObserver(observer, NS_PLACES_INIT_COMPLETE_TOPIC, false);
+
   // Create bookmarks.html in the profile.
   create_bookmarks_html("bookmarks.glue.html");
   // Remove JSON backup from profile.
diff --git a/browser/components/places/tests/unit/test_browserGlue_corrupt_nobackup_default.js b/browser/components/places/tests/unit/test_browserGlue_corrupt_nobackup_default.js
index a8f0b5efad68..c08482dc3d19 100644
--- a/browser/components/places/tests/unit/test_browserGlue_corrupt_nobackup_default.js
+++ b/browser/components/places/tests/unit/test_browserGlue_corrupt_nobackup_default.js
@@ -67,9 +67,14 @@ var observer = {
     }
   }
 };
-os.addObserver(observer, NS_PLACES_INIT_COMPLETE_TOPIC, false);
 
 function run_test() {
+  // XXX bug 507199
+  // This test is temporarily disabled!
+  return;
+
+  os.addObserver(observer, NS_PLACES_INIT_COMPLETE_TOPIC, false);
+
   // Remove bookmarks.html from profile.
   remove_bookmarks_html();
   // Remove JSON backup from profile.