--- a/browser/extensions/pdfjs/components/PdfStreamConverter.js
+++ b/browser/extensions/pdfjs/components/PdfStreamConverter.js
@@ -13,16 +13,17 @@ const Cu = Components.utils;
 const MOZ_CENTRAL = true;
 const PDFJS_EVENT_ID = 'pdf.js.message';
 const PDF_CONTENT_TYPE = 'application/pdf';
 const PREF_PREFIX = 'pdfjs';
 const PDF_VIEWER_WEB_PAGE = 'resource://pdf.js/web/viewer.html';
 const MAX_DATABASE_LENGTH = 4096;
 const FIREFOX_ID = '{ec8030f7-c20a-464f-9b0e-13a3a9e97384}';
 const SEAMONKEY_ID = '{92650c4d-4b8e-4d2a-b7eb-24ecf4f6b63a}';
+const METRO_ID = '{99bceaaa-e3c6-48c1-b981-ef9b46b67d60}';
 
 Cu.import('resource://gre/modules/XPCOMUtils.jsm');
 Cu.import('resource://gre/modules/Services.jsm');
 Cu.import('resource://gre/modules/NetUtil.jsm');
 
 
 let appInfo = Cc['@mozilla.org/xre/app-info;1']
                   .getService(Ci.nsIXULAppInfo);
@@ -31,17 +32,18 @@ let Svc = {};
 XPCOMUtils.defineLazyServiceGetter(Svc, 'mime',
                                    '@mozilla.org/mime;1',
                                    'nsIMIMEService');
 
 if (appInfo.ID === FIREFOX_ID) {
   privateBrowsing = Cc['@mozilla.org/privatebrowsing;1']
                           .getService(Ci.nsIPrivateBrowsingService);
   inPrivateBrowsing = privateBrowsing.privateBrowsingEnabled;
-} else if (appInfo.ID === SEAMONKEY_ID) {
+} else if (appInfo.ID === SEAMONKEY_ID ||
+           appInfo.ID === METRO_ID) {
   privateBrowsing = null;
   inPrivateBrowsing = false;
 }
 
 function getBoolPref(pref, def) {
   try {
     return Services.prefs.getBoolPref(pref);
   } catch (ex) {

--- a/services/sync/SyncComponents.manifest
+++ b/services/sync/SyncComponents.manifest
@@ -3,22 +3,23 @@
 # so in order to prevent the instructions from being processed for WebappRT,
 # we need to restrict them to the applications that depend on them, i.e.:
 #
 #   b2g:            {3c2e2abc-06d4-11e1-ac3b-374f68613e61}
 #   browser:        {ec8030f7-c20a-464f-9b0e-13a3a9e97384}
 #   mobile/android: {aa3c5121-dab2-40e2-81ca-7ea25febc110}
 #   mobile/xul:     {a23983c0-fd0e-11dc-95ff-0800200c9a66}
 #   suite (comm):   {92650c4d-4b8e-4d2a-b7eb-24ecf4f6b63a}
+#   metro browser:  {99bceaaa-e3c6-48c1-b981-ef9b46b67d60}
 #
 # In theory we should do this for all these instructions, but in practice it is
 # sufficient to do it for the app-startup one, and the file is simpler that way.
 
 # Weave.js
 component {74b89fb0-f200-4ae8-a3ec-dd164117f6de} Weave.js
 contract @mozilla.org/weave/service;1 {74b89fb0-f200-4ae8-a3ec-dd164117f6de}
-category app-startup WeaveService service,@mozilla.org/weave/service;1 application={3c2e2abc-06d4-11e1-ac3b-374f68613e61} application={ec8030f7-c20a-464f-9b0e-13a3a9e97384} application={aa3c5121-dab2-40e2-81ca-7ea25febc110} application={a23983c0-fd0e-11dc-95ff-0800200c9a66} application={92650c4d-4b8e-4d2a-b7eb-24ecf4f6b63a}
+category app-startup WeaveService service,@mozilla.org/weave/service;1 application={3c2e2abc-06d4-11e1-ac3b-374f68613e61} application={ec8030f7-c20a-464f-9b0e-13a3a9e97384} application={aa3c5121-dab2-40e2-81ca-7ea25febc110} application={a23983c0-fd0e-11dc-95ff-0800200c9a66} application={92650c4d-4b8e-4d2a-b7eb-24ecf4f6b63a} application={99bceaaa-e3c6-48c1-b981-ef9b46b67d60}
 component {d28f8a0b-95da-48f4-b712-caf37097be41} Weave.js
 contract @mozilla.org/network/protocol/about;1?what=sync-log {d28f8a0b-95da-48f4-b712-caf37097be41}
 # Register resource aliases
 resource services-sync resource:///modules/services-sync/
 resource services-common resource:///modules/services-common/
 resource services-crypto resource:///modules/services-crypto/