diff --git a/core/modules/saver-handler.js b/core/modules/saver-handler.js
index a4b7f4a4e..e2ac21361 100644
--- a/core/modules/saver-handler.js
+++ b/core/modules/saver-handler.js
@@ -197,8 +197,12 @@ SaverHandler.prototype.isDirty = function() {
 Update the document body with the class "tc-dirty" if the wiki has unsaved/unsynced changes
 */
 SaverHandler.prototype.updateDirtyStatus = function() {
+	var self = this;
 	if($tw.browser) {
 		$tw.utils.toggleClass(document.body,"tc-dirty",this.isDirty());
+		$tw.utils.each($tw.windows,function(win) {
+			$tw.utils.toggleClass(win.document.body,"tc-dirty",self.isDirty());
+		});
 	}
 };
 
diff --git a/core/modules/startup/windows.js b/core/modules/startup/windows.js
index 5c867f74d..75786d026 100644
--- a/core/modules/startup/windows.js
+++ b/core/modules/startup/windows.js
@@ -19,7 +19,7 @@ exports.after = ["startup"];
 exports.synchronous = true;
 
 // Global to keep track of open windows (hashmap by title)
-var windows = {};
+$tw.windows = {};
 
 exports.startup = function() {
 	// Handle open window message
@@ -44,7 +44,7 @@ exports.startup = function() {
 		catch(e) {
 			return;
 		}
-		windows[title] = srcWindow;
+		$tw.windows[title] = srcWindow;
 		// Check for reopening the same window
 		if(srcWindow.haveInitialisedWindow) {
 			return;
@@ -54,7 +54,7 @@ exports.startup = function() {
 		srcDocument.close();
 		srcDocument.title = windowTitle;
 		srcWindow.addEventListener("beforeunload",function(event) {
-			delete windows[title];
+			delete $tw.windows[title];
 			$tw.wiki.removeEventListener("change",refreshHandler);
 		},false);
 		// Set up the styles
@@ -90,7 +90,7 @@ exports.startup = function() {
 	});
 	// Close open windows when unloading main window
 	$tw.addUnloadTask(function() {
-		$tw.utils.each(windows,function(win) {
+		$tw.utils.each($tw.windows,function(win) {
 			win.close();
 		});
 	});