diff --git a/layout/tools/reftest/reftest-content.js b/layout/tools/reftest/reftest-content.js
index 7310f652e630..158795ae8075 100644
--- a/layout/tools/reftest/reftest-content.js
+++ b/layout/tools/reftest/reftest-content.js
@@ -124,7 +124,7 @@ function OnInitialLoad()
     LogInfo("Using browser remote="+ gBrowserIsRemote +"\n");
 }
 
-function SetFailureTimeout(cb, timeout)
+function SetFailureTimeout(cb, timeout, uri)
 {
   var targetTime = Date.now() + timeout;
 
@@ -139,6 +139,11 @@ function SetFailureTimeout(cb, timeout)
     }
   }
 
+  // Once OnDocumentLoad is called to handle the 'load' event it will update
+  // this error message to reflect what stage of the processing it has reached
+  // as it advances to each stage in turn.
+  gFailureReason = "timed out after " + timeout +
+                   " ms waiting for 'load' event for " + uri;
   gFailureTimeout = setTimeout(wrapper, timeout);
 }
 
@@ -164,7 +169,7 @@ function StartTestURI(type, uri, timeout)
     if (gFailureTimeout != null) {
         SendException("program error managing timeouts\n");
     }
-    SetFailureTimeout(LoadFailed, timeout);
+    SetFailureTimeout(LoadFailed, timeout, uri);
 
     LoadURI(gCurrentURL);
 }
diff --git a/layout/tools/reftest/reftest.jsm b/layout/tools/reftest/reftest.jsm
index 57e5f2214f55..397ba25f25c2 100644
--- a/layout/tools/reftest/reftest.jsm
+++ b/layout/tools/reftest/reftest.jsm
@@ -1172,10 +1172,14 @@ function RecordResult(testRunTime, errorMsg, typeSpecificResults)
 function LoadFailed(why)
 {
     ++g.testResults.FailedLoad;
-    // Once bug 896840 is fixed, this can go away, but for now it will give log
-    // output that is TBPL starable for bug 789751 and bug 720452.
     if (!why) {
-        logger.error("load failed with unknown reason");
+        // reftest-content.js sets an initial reason before it sets the
+        // timeout that will call us with the currently set reason, so we
+        // should never get here.  If we do then there's a logic error
+        // somewhere.  Perhaps tests are somehow running overlapped and the
+        // timeout for one test is not being cleared before the timeout for
+        // another is set?  Maybe there's some sort of race?
+        logger.error("load failed with unknown reason (we should always have a reason!)");
     }
     logger.testStatus(g.urls[0].identifier, "load failed: " + why, "FAIL", "PASS");
     FlushTestBuffer();