diff --git a/dom/browser-element/BrowserElementChildPreload.js b/dom/browser-element/BrowserElementChildPreload.js
index 0d4c5430ac94..d674980af03c 100644
--- a/dom/browser-element/BrowserElementChildPreload.js
+++ b/dom/browser-element/BrowserElementChildPreload.js
@@ -1567,7 +1567,11 @@ BrowserElementChild.prototype = {
       location = Cc["@mozilla.org/docshell/urifixup;1"]
         .getService(Ci.nsIURIFixup).createExposableURI(location);
 
-      sendAsyncMsg('locationchange', { _payload_: location.spec });
+      var webNav = docShell.QueryInterface(Ci.nsIWebNavigation);
+
+      sendAsyncMsg('locationchange', { url: location.spec,
+                                       canGoBack: webNav.canGoBack,
+                                       canGoForward: webNav.canGoForward });
     },
 
     onStateChange: function(webProgress, request, stateFlags, status) {
diff --git a/dom/browser-element/mochitest/browserElement_BackForward.js b/dom/browser-element/mochitest/browserElement_BackForward.js
index e3d23a81dd39..26b6344c46bd 100644
--- a/dom/browser-element/mochitest/browserElement_BackForward.js
+++ b/dom/browser-element/mochitest/browserElement_BackForward.js
@@ -70,7 +70,9 @@ function test3() {
 
 function test4() {
   addOneShotIframeEventListener('mozbrowserlocationchange', function(e) {
-    is(e.detail, browserElementTestHelpers.emptyPage3);
+    is(e.detail.url, browserElementTestHelpers.emptyPage3);
+    is(e.detail.canGoBack, true);
+    is(e.detail.canGoForward, false);
     checkCanGoBackAndForward(true, false, test5);
   });
 
@@ -81,7 +83,9 @@ function test4() {
 
 function test5() {
   addOneShotIframeEventListener('mozbrowserlocationchange', function(e) {
-    is(e.detail, browserElementTestHelpers.emptyPage2);
+    is(e.detail.url, browserElementTestHelpers.emptyPage2);
+    is(e.detail.canGoBack, true);
+    is(e.detail.canGoForward, true);
     checkCanGoBackAndForward(true, true, test6);
   });
   iframe.goBack();
@@ -89,7 +93,9 @@ function test5() {
 
 function test6() {
   addOneShotIframeEventListener('mozbrowserlocationchange', function(e) {
-    is(e.detail, browserElementTestHelpers.emptyPage1);
+    is(e.detail.url, browserElementTestHelpers.emptyPage1);
+    is(e.detail.canGoBack, false);
+    is(e.detail.canGoForward, true);
     checkCanGoBackAndForward(false, true, SimpleTest.finish);
   });
   iframe.goBack();
diff --git a/dom/browser-element/mochitest/browserElement_BrowserWindowNamespace.js b/dom/browser-element/mochitest/browserElement_BrowserWindowNamespace.js
index 1ea15109896f..b326028067ad 100644
--- a/dom/browser-element/mochitest/browserElement_BrowserWindowNamespace.js
+++ b/dom/browser-element/mochitest/browserElement_BrowserWindowNamespace.js
@@ -24,12 +24,12 @@ function runTest() {
     document.body.appendChild(e.detail.frameElement);
 
     e.detail.frameElement.addEventListener('mozbrowserlocationchange', function(e) {
-      if (e.detail == "http://example.com/#2") {
+      if (e.detail.url == "http://example.com/#2") {
         ok(true, "Got locationchange to http://example.com/#2");
         SimpleTest.finish();
       }
       else {
-        ok(true, "Got locationchange to " + e.detail);
+        ok(true, "Got locationchange to " + e.detail.url);
       }
     });
 
diff --git a/dom/browser-element/mochitest/browserElement_DataURI.js b/dom/browser-element/mochitest/browserElement_DataURI.js
index d2df39a20233..f57f4566a936 100644
--- a/dom/browser-element/mochitest/browserElement_DataURI.js
+++ b/dom/browser-element/mochitest/browserElement_DataURI.js
@@ -36,7 +36,7 @@ function runTest2() {
     ok(e.isTrusted, 'Event should be trusted.');
     ok(!sawLocationChange, 'Just one locationchange event.');
     ok(!sawLoadEnd, 'locationchange before load.');
-    is(e.detail, 'data:text/html,1', "event's reported location");
+    is(e.detail.url, 'data:text/html,1', "event's reported location");
     sawLocationChange = true;
   });
 
diff --git a/dom/browser-element/mochitest/browserElement_ExposableURI.js b/dom/browser-element/mochitest/browserElement_ExposableURI.js
index e38d809e0d25..435e11a807d7 100644
--- a/dom/browser-element/mochitest/browserElement_ExposableURI.js
+++ b/dom/browser-element/mochitest/browserElement_ExposableURI.js
@@ -13,7 +13,7 @@ var iframe;
 
 function testPassword() {
   function locationchange(e) {
-    var uri = e.detail;
+    var uri = e.detail.url;
     is(uri, 'http://mochi.test:8888/tests/dom/browser-element/mochitest/file_empty.html',
        "Username and password shouldn't be exposed in uri.");
     SimpleTest.finish();
@@ -33,7 +33,7 @@ function testWyciwyg() {
     if (locationChangeCount == 0) {
       locationChangeCount ++;
     } else if (locationChangeCount == 1) {
-      var uri = e.detail;
+      var uri = e.detail.url;
       is(uri, 'http://mochi.test:8888/tests/dom/browser-element/mochitest/file_wyciwyg.html', "Scheme in string shouldn't be wyciwyg");
       iframe.removeEventListener('mozbrowserlocationchange', locationchange);
       SimpleTest.executeSoon(testPassword);
diff --git a/dom/browser-element/mochitest/browserElement_FirstPaint.js b/dom/browser-element/mochitest/browserElement_FirstPaint.js
index 99b886c0f02e..ad67abc3aac0 100644
--- a/dom/browser-element/mochitest/browserElement_FirstPaint.js
+++ b/dom/browser-element/mochitest/browserElement_FirstPaint.js
@@ -24,13 +24,13 @@ function runTest() {
   });
 
   iframe.addEventListener('mozbrowserlocationchange', function(e) {
-    if (e.detail == browserElementTestHelpers.emptyPage1) {
+    if (e.detail.url == browserElementTestHelpers.emptyPage1) {
       gotFirstLocationChange = true;
       if (gotFirstPaint) {
         iframe.src = browserElementTestHelpers.emptyPage1 + '?2';
       }
     }
-    else if (e.detail.endsWith('?2')) {
+    else if (e.detail.url.endsWith('?2')) {
       SimpleTest.finish();
     }
   });
diff --git a/dom/browser-element/mochitest/browserElement_ForwardName.js b/dom/browser-element/mochitest/browserElement_ForwardName.js
index 5f4fe8b4863e..326c1ef248d2 100644
--- a/dom/browser-element/mochitest/browserElement_ForwardName.js
+++ b/dom/browser-element/mochitest/browserElement_ForwardName.js
@@ -20,8 +20,8 @@ function runTest() {
   });
 
   iframe.addEventListener('mozbrowserlocationchange', function(e) {
-    ok(true, "Got locationchange to " + e.detail);
-    if (e.detail.endsWith("ForwardName.html#finish")) {
+    ok(true, "Got locationchange to " + e.detail.url);
+    if (e.detail.url.endsWith("ForwardName.html#finish")) {
       SimpleTest.finish();
     }
   });
diff --git a/dom/browser-element/mochitest/browserElement_LoadEvents.js b/dom/browser-element/mochitest/browserElement_LoadEvents.js
index f08a0fad18de..8b43d8e753e5 100644
--- a/dom/browser-element/mochitest/browserElement_LoadEvents.js
+++ b/dom/browser-element/mochitest/browserElement_LoadEvents.js
@@ -38,7 +38,7 @@ function runTest() {
     seenLocationChange = true;
     ok(seenLoadStart, 'Location change after load start.');
     ok(!seenLoadEnd, 'Location change before load end.');
-    ok(e.detail, browserElementTestHelpers.emptyPage1, "event's reported location");
+    ok(e.detail.url, browserElementTestHelpers.emptyPage1, "event's reported location");
   }
 
   function loadend(e) {
@@ -91,7 +91,7 @@ function runTest2() {
     seenLocationChange = true;
     ok(seenLoadStart, 'Location change after load start.');
     ok(!seenLoadEnd, 'Location change before load end.');
-    ok(e.detail, browserElementTestHelpers.emptyPage2, "event's reported location");
+    ok(e.detail.url, browserElementTestHelpers.emptyPage2, "event's reported location");
   });
 
   iframe.addEventListener('mozbrowserloadend', function(e) {
diff --git a/dom/browser-element/mochitest/browserElement_PurgeHistory.js b/dom/browser-element/mochitest/browserElement_PurgeHistory.js
index dac013518537..4815f03e7e48 100644
--- a/dom/browser-element/mochitest/browserElement_PurgeHistory.js
+++ b/dom/browser-element/mochitest/browserElement_PurgeHistory.js
@@ -75,7 +75,7 @@ function test3() {
 
 function test4() {
   addOneShotIframeEventListener('mozbrowserlocationchange', function(e) {
-    is(e.detail, browserElementTestHelpers.emptyPage3);
+    is(e.detail.url, browserElementTestHelpers.emptyPage3);
     purgeHistory(SimpleTest.finish);
   });
 
diff --git a/dom/browser-element/mochitest/browserElement_SendEvent.js b/dom/browser-element/mochitest/browserElement_SendEvent.js
index 4d5816a18b17..a65d6f24fba8 100644
--- a/dom/browser-element/mochitest/browserElement_SendEvent.js
+++ b/dom/browser-element/mochitest/browserElement_SendEvent.js
@@ -35,7 +35,7 @@ function runTest() {
 
   iframe.addEventListener("mozbrowserlocationchange", function onlocchange(e) {
     var a = document.createElement("a");
-    a.href = e.detail;
+    a.href = e.detail.url;
 
     switch (a.hash) {
       case "#mousedown":
diff --git a/dom/browser-element/mochitest/browserElement_TargetTop.js b/dom/browser-element/mochitest/browserElement_TargetTop.js
index 9dd3340df9e2..54bad9c423a8 100644
--- a/dom/browser-element/mochitest/browserElement_TargetTop.js
+++ b/dom/browser-element/mochitest/browserElement_TargetTop.js
@@ -18,7 +18,7 @@ function runTest() {
   });
 
   iframe.addEventListener('mozbrowserlocationchange', function(e) {
-    if (/file_browserElement_TargetTop.html\?2$/.test(e.detail)) {
+    if (/file_browserElement_TargetTop.html\?2$/.test(e.detail.url)) {
       ok(true, 'Got the locationchange we were looking for.');
       SimpleTest.finish();
     }