diff --git a/chrome-extension/bg.js b/chrome-extension/bg.js
index 2157d58..f3935dd 100644
--- a/chrome-extension/bg.js
+++ b/chrome-extension/bg.js
@@ -3,7 +3,7 @@ var prefs = {};
 chrome.storage.local.get({callback: 'http://localhost:8080', key: 'chrome'}, function(o) { prefs = o; });
 
 chrome.storage.onChanged.addListener(function(changes) {
-    for (key in changes) {
+    for (var key in changes) {
         prefs[key] = changes[key].newValue;
     }
 });
@@ -16,6 +16,7 @@ function log(url, title, favicon){
     });
     var xhr = new XMLHttpRequest();
     xhr.open("POST", prefs.callback);
+    xhr.setRequestHeader("Content-Type", "application/json");
     xhr.send(data);
 }
 
diff --git a/firefox-addon/lib/main.js b/firefox-addon/lib/main.js
index f0926c4..7656850 100644
--- a/firefox-addon/lib/main.js
+++ b/firefox-addon/lib/main.js
@@ -15,6 +15,7 @@ function log(url, title, favicon){
     });
     var xhr = new XMLHttpRequest();
     xhr.open("POST", prefs.callback);
+    xhr.setRequestHeader("Content-Type", "application/json");
     xhr.send(data);
 }
 
@@ -26,7 +27,7 @@ function logTab(tab) {
     }
 }
 
-tabs.on("activate", function () { logTab(tabs.activeTab) });
+tabs.on("activate", function () { logTab(tabs.activeTab); });
 
 tabs.on("pageshow", logTab );
 
@@ -38,4 +39,4 @@ windows.on("activate", function (window) {
     logTab(tabs.activeTab) ;
 });
 
-windows.on("deactivate", function (window) { log(null, null, null) });
+windows.on("deactivate", function (window) { log(null, null, null); });