diff -r 000000000000 -r 6474c204b198 browser/devtools/netmonitor/test/browser_net_cyrillic-01.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/devtools/netmonitor/test/browser_net_cyrillic-01.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,44 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Tests if cyrillic text is rendered correctly in the source editor.
+ */
+
+function test() {
+  initNetMonitor(CYRILLIC_URL).then(([aTab, aDebuggee, aMonitor]) => {
+    info("Starting test... ");
+
+    let { document, Editor, NetMonitorView } = aMonitor.panelWin;
+    let { RequestsMenu } = NetMonitorView;
+
+    RequestsMenu.lazyUpdate = false;
+
+    waitForNetworkEvents(aMonitor, 1).then(() => {
+      verifyRequestItemTarget(RequestsMenu.getItemAtIndex(0),
+        "GET", CONTENT_TYPE_SJS + "?fmt=txt", {
+          status: 200,
+          statusText: "DA DA DA"
+        });
+
+      EventUtils.sendMouseEvent({ type: "mousedown" },
+        document.getElementById("details-pane-toggle"));
+      EventUtils.sendMouseEvent({ type: "mousedown" },
+        document.querySelectorAll("#details-pane tab")[3]);
+
+      let RESPONSE_BODY_DISPLAYED = aMonitor.panelWin.EVENTS.RESPONSE_BODY_DISPLAYED;
+      waitFor(aMonitor.panelWin, RESPONSE_BODY_DISPLAYED).then(() =>
+        NetMonitorView.editor("#response-content-textarea")
+      ).then((aEditor) => {
+        is(aEditor.getText().indexOf("\u044F"), 26, // я
+          "The text shown in the source editor is incorrect.");
+        is(aEditor.getMode(), Editor.modes.text,
+          "The mode active in the source editor is incorrect.");
+
+        teardown(aMonitor).then(finish);
+      });
+    });
+
+    aDebuggee.performRequests();
+  });
+}