diff --git a/ext/data/config.html b/ext/data/config.html
index 1ab1b8b..24de71c 100644
--- a/ext/data/config.html
+++ b/ext/data/config.html
@@ -16,12 +16,14 @@ <h2>Stored sites:</h2>
     <thead><tr><th>sitename<th>(matching)<th>count<th>type<th>ver
 <tbody>
 </table>
+<button id="export_mpsites">export</button>
 <script src="./js/jquery-2.1.3.min.js"></script>
 <script type="text/javascript">
 
 (function(){
 
  var stored_sites={};
+ var username="";
 
 function save_sites_to_backend() {
     var event = document.createEvent('CustomEvent');
@@ -90,8 +92,9 @@ <h2>Stored sites:</h2>
 }
 
 window.addEventListener('masterpassword-configload', function(e){
-    stored_sites = e.detail;
-    $.each(e.detail, function(domain,v){
+    stored_sites = e.detail.sites;
+    username = e.detail.username;
+    $.each(stored_sites, function(domain,v){
         $.each(v, function(site, settings){
             stored_sites_table_append(domain,site,settings.type,settings.generation,"3")
         });
@@ -159,6 +162,66 @@ <h2>Stored sites:</h2>
 
 });
 
+$('#export_mpsites').on('click',function(){
+    var x = make_mpsites();
+    start_data_download(x, 'firefox.mpsites');
+});
+
+function make_mpsites() {
+    var a=[ '# Master Password site export\n',
+        '#     Export of site names and stored passwords (unless device-private) encrypted with the master key.\n',
+        '#\n',
+        '##\n',
+        '# Format: 1\n',
+        '# Date: 2015-03-24T14:44:51Z\n',
+        '# User Name: '+username+'\n',
+        '# Full Name: '+username+'\n',
+        '# Avatar: 0\n',
+        '# Key ID:\n',
+        '# Version: 2.2\n',
+        '# Algorithm: 3\n',
+        '# Default Type: 17\n',
+        '# Passwords: PROTECTED\n',
+        '##\n',
+        '#\n',
+        '#               Last     Times  Password                      Login\t                     Site\tSite\n',
+        '#               used      used      type                       name\t                     name\tpassword\n'];
+
+    $.each(stored_sites, function(domain,v){
+        $.each(v, function(site, settings){
+            var x;
+            switch(settings.type){
+                case 's': x='20'; break;
+                case 'x': x='16'; break;
+                case 'i': x='21'; break;
+                case 'b': x='19'; break;
+                case 'p': x='31'; break;
+                case 'n': x='30'; break;
+                case 'l': x='17'; break;
+                case 'm': x='18'; break;
+                default: throw "unknown password type";
+            }
+            x+=':3:'+settings.generation;
+            while (x.length<8) x=" "+x;
+            while (site.length<25) site=" "+site;
+            a.push('2015-03-23T13:06:35Z         0  '+x+'                           \t'+site+'\t\n');
+        });
+    });
+    return a;
+}
+
+function start_data_download(stringarr,filename) {
+    var a = window.document.createElement('a');
+    a.href = window.URL.createObjectURL(new Blob(stringarr, {type: 'text/plain'}));
+    a.download = filename;
+
+    // Append anchor to body.
+    document.body.appendChild(a)
+    a.click();
+
+    // Remove anchor from body
+    document.body.removeChild(a)
+}
 
 
 }());
diff --git a/ext/lib/main.js b/ext/lib/main.js
index 1091b50..b6fe769 100644
--- a/ext/lib/main.js
+++ b/ext/lib/main.js
@@ -69,7 +69,7 @@ function createPanel() {
                 if (! /^resource:.*config\.html$/.test(tab.url)) return;
                 var worker = tab.attach({ contentScriptFile: self.data.url('config-cs.js') });
                 worker.port.on('configload', function(m) {
-                    worker.port.emit('configload',session_store.sites);
+                    worker.port.emit('configload', {sites:session_store.sites, username:session_store.username});
                 });
                 worker.port.on('configstore', function(d) {
                     session_store.sites = d;