--- a/devtools/client/framework/target.js
+++ b/devtools/client/framework/target.js
@@ -473,26 +473,28 @@ TabTarget.prototype = {
       // We have to filter message to ensure that this detach is for this tab
       if (aPacket.from == this._form.actor) {
         this.destroy();
       }
     };
     this.client.addListener("tabDetached", this._onTabDetached);
 
     this._onTabNavigated = (aType, aPacket) => {
-      // Update the title and url on tabNavigated event.
-      this._url = aPacket.url;
-      this._title = aPacket.title;
-
       let event = Object.create(null);
       event.url = aPacket.url;
       event.title = aPacket.title;
       event.nativeConsoleAPI = aPacket.nativeConsoleAPI;
       event.isFrameSwitching = aPacket.isFrameSwitching;
 
+      if (!aPacket.isFrameSwitching) {
+        // Update the title and url unless this is a frame switch.
+        this._url = aPacket.url;
+        this._title = aPacket.title;
+      }
+
       // Send any stored event payload (DOMWindow or nsIRequest) for backwards
       // compatibility with non-remotable tools.
       if (aPacket.state == "start") {
         event._navPayload = this._navRequest;
         this.emit("will-navigate", event);
         this._navRequest = null;
       } else {
         event._navPayload = this._navWindow;

--- a/devtools/client/framework/test/browser.ini
+++ b/devtools/client/framework/test/browser.ini
@@ -2,16 +2,17 @@
 tags = devtools
 subsuite = devtools
 support-files =
   browser_toolbox_options_disable_js.html
   browser_toolbox_options_disable_js_iframe.html
   browser_toolbox_options_disable_cache.sjs
   browser_toolbox_sidebar_tool.xul
   browser_toolbox_window_title_changes_page.html
+  browser_toolbox_window_title_frame_select_page.html
   code_math.js
   code_ugly.js
   head.js
   shared-head.js
   shared-redux-head.js
   helper_disable_cache.js
   doc_theme.css
   doc_viewsource.html
@@ -69,13 +70,14 @@ skip-if = e10s # Bug 1069044 - destroyIn
 [browser_toolbox_view_source_01.js]
 [browser_toolbox_view_source_02.js]
 [browser_toolbox_view_source_03.js]
 [browser_toolbox_view_source_04.js]
 [browser_toolbox_window_reload_target.js]
 [browser_toolbox_window_shortcuts.js]
 skip-if = os == "mac" && os_version == "10.8" || os == "win" && os_version == "5.1" # Bug 851129 - Re-enable browser_toolbox_window_shortcuts.js test after leaks are fixed
 [browser_toolbox_window_title_changes.js]
+[browser_toolbox_window_title_frame_select.js]
 [browser_toolbox_zoom.js]
 [browser_two_tabs.js]
 skip-if = e10s && debug && os == 'win' # Bug 1231869
 # We want this test to run for mochitest-dt as well, so we include it here:
 [../../../../browser/base/content/test/general/browser_parsable_css.js]

new file mode 100644
--- /dev/null
+++ b/devtools/client/framework/test/browser_toolbox_window_title_frame_select.js
@@ -0,0 +1,72 @@
+/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
+/* vim: set ft=javascript ts=2 et sw=2 tw=80: */
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/* import-globals-from shared-head.js */
+
+"use strict";
+
+/**
+ * Check that the detached devtools window title is not updated when switching
+ * the selected frame.
+ */
+
+var {Toolbox} = require("devtools/client/framework/toolbox");
+const URL = URL_ROOT + "browser_toolbox_window_title_frame_select_page.html";
+const IFRAME_URL = URL_ROOT + "browser_toolbox_window_title_changes_page.html";
+
+add_task(function* () {
+  Services.prefs.setBoolPref("devtools.command-button-frames.enabled", true);
+
+  yield addTab(URL);
+  let target = TargetFactory.forTab(gBrowser.selectedTab);
+  let toolbox = yield gDevTools.showToolbox(target, null,
+    Toolbox.HostType.BOTTOM);
+
+  yield toolbox.selectTool("inspector");
+  yield toolbox.switchHost(Toolbox.HostType.WINDOW);
+
+  is(getTitle(), "Inspector - Page title",
+    "Devtools title correct after switching to detached window host");
+
+  // Verify that the frame list button is visible and populated
+  let btn = toolbox.doc.getElementById("command-button-frames");
+  let frames = Array.slice(btn.firstChild.querySelectorAll("[data-window-id]"));
+  is(frames.length, 2, "We have both frames in the list");
+
+  let topFrameBtn = frames.filter(b => b.getAttribute("label") == URL)[0];
+  let iframeBtn = frames.filter(b => b.getAttribute("label") == IFRAME_URL)[0];
+  ok(topFrameBtn, "Got top level document in the list");
+  ok(iframeBtn, "Got iframe document in the list");
+
+  // Listen to will-navigate to check if the view is empty
+  let willNavigate = toolbox.target.once("will-navigate");
+
+  // Only select the iframe after we are able to select an element from the top
+  // level document.
+  let newRoot = toolbox.getPanel("inspector").once("new-root");
+  info("Select the iframe");
+  iframeBtn.click();
+
+  yield willNavigate;
+  yield newRoot;
+
+  info("Navigation to the iframe is done, the inspector should be back up");
+  is(getTitle(), "Inspector - Page title",
+    "Devtools title was not updated after changing inspected frame");
+
+  info("Cleanup toolbox and test preferences.");
+  yield toolbox.destroy();
+  toolbox = null;
+  gBrowser.removeCurrentTab();
+  Services.prefs.clearUserPref("devtools.toolbox.host");
+  Services.prefs.clearUserPref("devtools.toolbox.selectedTool");
+  Services.prefs.clearUserPref("devtools.toolbox.sideEnabled");
+  Services.prefs.clearUserPref("devtools.command-button-frames.enabled");
+  finish();
+});
+
+function getTitle() {
+  return Services.wm.getMostRecentWindow("devtools:toolbox").document.title;
+}

new file mode 100644
--- /dev/null
+++ b/devtools/client/framework/test/browser_toolbox_window_title_frame_select_page.html
@@ -0,0 +1,11 @@
+<!DOCTYPE HTML>
+<html>
+  <head>
+    <meta charset="UTF-8">
+    <title>Page title</title>
+    <!-- Any copyright is dedicated to the Public Domain.
+         http://creativecommons.org/publicdomain/zero/1.0/ -->
+    <iframe src="browser_toolbox_window_title_changes_page.html"></iframe>
+  </head>
+  <body></body>
+</html>