diff --git a/dom/webidl/PerformanceTiming.webidl b/dom/webidl/PerformanceTiming.webidl
index 452221e6a0d1..53e5b8f24f26 100644
--- a/dom/webidl/PerformanceTiming.webidl
+++ b/dom/webidl/PerformanceTiming.webidl
@@ -31,6 +31,7 @@ interface PerformanceTiming {
   readonly attribute unsigned long long connectStart;
   [Infallible]
   readonly attribute unsigned long long connectEnd;
+  // secureConnectionStart will be implemneted in bug 772589
   // [Infallible]
   // readonly attribute unsigned long long secureConnectionStart;
   [Infallible]