diff --git a/browser/base/content/browser.xul b/browser/base/content/browser.xul
index 428a9777495..177eddf056e 100644
--- a/browser/base/content/browser.xul
+++ b/browser/base/content/browser.xul
@@ -8,7 +8,7 @@
 
 <?xml-stylesheet href="chrome://browser/content/browser.css" type="text/css"?>
 <?xml-stylesheet href="chrome://browser/content/places/places.css" type="text/css"?>
-<?xml-stylesheet href="chrome://devtools/skin/common.css" type="text/css"?>
+<?xml-stylesheet href="chrome://devtools/skin/devtools-browser.css" type="text/css"?>
 <?xml-stylesheet href="chrome://browser/skin/controlcenter/panel.css" type="text/css"?>
 <?xml-stylesheet href="chrome://browser/skin/customizableui/panelUIOverlay.css" type="text/css"?>
 <?xml-stylesheet href="chrome://browser/skin/" type="text/css"?>
diff --git a/browser/locales/Makefile.in b/browser/locales/Makefile.in
index 6f75776caf6..f7e680767a8 100644
--- a/browser/locales/Makefile.in
+++ b/browser/locales/Makefile.in
@@ -189,7 +189,7 @@ ident:
 merge-%:
 ifdef LOCALE_MERGEDIR
 	$(RM) -rf $(LOCALE_MERGEDIR)
-	MACOSX_DEPLOYMENT_TARGET= compare-locales -m $(LOCALE_MERGEDIR) $(srcdir)/l10n.ini $(L10NBASEDIR) $*
+	$(topsrcdir)/mach compare-locales --merge-dir $(LOCALE_MERGEDIR) $*
 endif
 	@echo
 
diff --git a/browser/locales/en-US/chrome/browser/loop/loop.properties b/browser/locales/en-US/chrome/browser/loop/loop.properties
index 34906a9e830..ba9bbe2e088 100644
--- a/browser/locales/en-US/chrome/browser/loop/loop.properties
+++ b/browser/locales/en-US/chrome/browser/loop/loop.properties
@@ -12,7 +12,7 @@ clientSuperShortname=Hello
 ## LOCALIZATION_NOTE(loopMenuItem_label): Label of the menu item that is placed
 ## inside the browser 'Tools' menu. Use the unicode ellipsis char, \u2026, or
 ## use "..." if \u2026 doesn't suit traditions in your locale.
-loopMenuItem_label=Start a conversation…
+loopMenuItem_label=Start a Conversation…
 loopMenuItem_accesskey=t
 
 ## LOCALIZATION_NOTE(sign_in_again_title_line_one, sign_in_again_title_line_two2):
diff --git a/devtools/bootstrap.js b/devtools/bootstrap.js
index 109d56a3f77..46c1fe3026d 100644
--- a/devtools/bootstrap.js
+++ b/devtools/bootstrap.js
@@ -80,6 +80,10 @@ function reload(event) {
   // Ask the loader to update itself and reopen the toolbox if needed
   const {devtools} = Cu.import("resource://devtools/shared/Loader.jsm", {});
   devtools.reload(reloadToolbox);
+
+  // Also tells gDevTools to reload its dependencies
+  const {gDevTools} = Cu.import("resource://devtools/client/framework/gDevTools.jsm", {});
+  gDevTools.reload();
 }
 
 let listener;
diff --git a/devtools/client/debugger/test/mochitest/browser.ini b/devtools/client/debugger/test/mochitest/browser.ini
index 0b564dfad4f..011cfaa874f 100644
--- a/devtools/client/debugger/test/mochitest/browser.ini
+++ b/devtools/client/debugger/test/mochitest/browser.ini
@@ -326,6 +326,8 @@ skip-if = e10s && debug
 skip-if = e10s && debug
 [browser_dbg_parser-10.js]
 skip-if = e10s && debug
+[browser_dbg_parser-11.js]
+skip-if = e10s && debug
 [browser_dbg_pause-exceptions-01.js]
 skip-if = e10s && debug
 [browser_dbg_pause-exceptions-02.js]
diff --git a/devtools/client/debugger/test/mochitest/browser_dbg_parser-11.js b/devtools/client/debugger/test/mochitest/browser_dbg_parser-11.js
new file mode 100644
index 00000000000..428cab8e070
--- /dev/null
+++ b/devtools/client/debugger/test/mochitest/browser_dbg_parser-11.js
@@ -0,0 +1,39 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+/**
+ * Checks if self-closing <script/> tags are parsed by Parser.jsm
+ */
+
+function test() {
+  let { Parser } = Cu.import("resource://devtools/shared/Parser.jsm", {});
+
+  let source = [
+    '<script type="text/javascript" src="chrome://foo.js"/>',
+    '<script type="application/javascript;version=1.8" src="chrome://baz.js"/>',
+    '<script async defer src="chrome://foobar.js"/>',
+    '<script type="application/javascript"/>"hello third"',
+    '<script type="application/javascript">"hello fourth"</script>',
+  ].join("\n");
+  let parser = new Parser();
+  let parsed = parser.get(source);
+
+  is(parser.errors.length, 0,
+    "There should be no errors logged when parsing.");
+  is(parsed.scriptCount, 5,
+    "There should be 5 scripts parsed in the parent HTML source.");
+
+  is(parsed.getScriptInfo(source.indexOf("foo.js\"/>") + 1).toSource(), "({start:-1, length:-1, index:-1})",
+    "the first script is empty");
+  is(parsed.getScriptInfo(source.indexOf("baz.js\"/>") + 1).toSource(), "({start:-1, length:-1, index:-1})",
+    "the second script is empty");
+  is(parsed.getScriptInfo(source.indexOf("foobar.js\"/>") + 1).toSource(), "({start:-1, length:-1, index:-1})",
+    "the third script is empty");
+
+  is(parsed.getScriptInfo(source.indexOf("hello third!")).toSource(), "({start:-1, length:-1, index:-1})",
+    "Inline script on self-closing tag not considered a script");
+  is(parsed.getScriptInfo(source.indexOf("hello fourth")).toSource(), "({start:267, length:14, index:4})",
+    "The fourth script was located correctly.");
+
+  finish();
+}
diff --git a/devtools/client/eyedropper/eyedropper.xul b/devtools/client/eyedropper/eyedropper.xul
index b7c70e3b91e..7a5d1fe2f15 100644
--- a/devtools/client/eyedropper/eyedropper.xul
+++ b/devtools/client/eyedropper/eyedropper.xul
@@ -9,7 +9,10 @@
 <?xml-stylesheet href="chrome://devtools/skin/common.css"?>
 <?xml-stylesheet href="chrome://devtools/skin/eyedropper.css" type="text/css"?>
 
-<window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+<window xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
+        no-theme="true">
+  <script type="application/javascript;version=1.8"
+          src="chrome://devtools/content/shared/theme-switching.js"/>
   <commandset id="eyedropper-commandset">
     <command id="eyedropper-cmd-close"
              oncommand="void(0);"/>
diff --git a/devtools/client/framework/gDevTools.jsm b/devtools/client/framework/gDevTools.jsm
index d90030d132a..8014d65930f 100644
--- a/devtools/client/framework/gDevTools.jsm
+++ b/devtools/client/framework/gDevTools.jsm
@@ -10,21 +10,34 @@ const { classes: Cc, interfaces: Ci, utils: Cu } = Components;
 
 Cu.import("resource://gre/modules/XPCOMUtils.jsm");
 Cu.import("resource://gre/modules/Services.jsm");
-const { require, loader } = Cu.import("resource://devtools/shared/Loader.jsm", {});
-const promise = require("promise");
-// Load target and toolbox lazily as they need gDevTools to be fully initialized
-loader.lazyRequireGetter(this, "TargetFactory", "devtools/client/framework/target", true);
-loader.lazyRequireGetter(this, "Toolbox", "devtools/client/framework/toolbox", true);
 
-XPCOMUtils.defineLazyModuleGetter(this, "console",
-                                  "resource://gre/modules/Console.jsm");
-XPCOMUtils.defineLazyModuleGetter(this, "CustomizableUI",
-                                  "resource:///modules/CustomizableUI.jsm");
-loader.lazyRequireGetter(this, "DebuggerServer", "devtools/server/main", true);
-loader.lazyRequireGetter(this, "DebuggerClient", "devtools/shared/client/main", true);
+// Make most dependencies be reloadable so that the reload addon
+// can update all of them while keeping gDevTools.jsm as-is
+// Bug 1188405 is going to refactor this JSM into a commonjs module
+// so that it can be reloaded as other modules.
+let require, loader, promise, DefaultTools, DefaultThemes;
+let loadDependencies = () => {
+  let l = Cu.import("resource://devtools/shared/Loader.jsm", {});
+  require = l.require;
+  loader = l.loader;
+  promise = require("promise");
+  // Load target and toolbox lazily as they need gDevTools to be fully initialized
+  loader.lazyRequireGetter(this, "TargetFactory", "devtools/client/framework/target", true);
+  loader.lazyRequireGetter(this, "Toolbox", "devtools/client/framework/toolbox", true);
+
+  XPCOMUtils.defineLazyModuleGetter(this, "console",
+                                    "resource://gre/modules/Console.jsm");
+  XPCOMUtils.defineLazyModuleGetter(this, "CustomizableUI",
+                                    "resource:///modules/CustomizableUI.jsm");
+  loader.lazyRequireGetter(this, "DebuggerServer", "devtools/server/main", true);
+  loader.lazyRequireGetter(this, "DebuggerClient", "devtools/shared/client/main", true);
+
+  let d = require("devtools/client/definitions");
+  DefaultTools = d.defaultTools;
+  DefaultThemes = d.defaultThemes;
+};
+loadDependencies();
 
-const {defaultTools: DefaultTools, defaultThemes: DefaultThemes} =
-  require("devtools/client/definitions");
 const EventEmitter = require("devtools/shared/event-emitter");
 const Telemetry = require("devtools/client/shared/telemetry");
 const {JsonView} = require("devtools/client/jsonview/main");
@@ -511,6 +524,11 @@ DevTools.prototype = {
     // Is taken care of by the gDevToolsBrowser.forgetBrowserWindow
   },
 
+  // Force reloading dependencies if the loader happens to have reloaded
+  reload() {
+    loadDependencies();
+  },
+
   /**
    * Iterator that yields each of the toolboxes.
    */
diff --git a/devtools/client/framework/toolbox.js b/devtools/client/framework/toolbox.js
index 8193982ca01..f98c0a1c796 100644
--- a/devtools/client/framework/toolbox.js
+++ b/devtools/client/framework/toolbox.js
@@ -356,7 +356,7 @@ Toolbox.prototype = {
       iframe.setAttribute("src", this._URL);
       iframe.setAttribute("aria-label", toolboxStrings("toolbox.label"));
       let domHelper = new DOMHelpers(iframe.contentWindow);
-      domHelper.onceDOMReady(() => domReady.resolve());
+      domHelper.onceDOMReady(() => domReady.resolve(), this._URL);
       // Optimization: fire up a few other things before waiting on
       // the iframe being ready (makes startup faster)
 
@@ -365,7 +365,6 @@ Toolbox.prototype = {
 
       // Attach the thread
       this._threadClient = yield attachThread(this);
-
       yield domReady.promise;
 
       this.isReady = true;
diff --git a/devtools/client/inspector/fonts/fonts.css b/devtools/client/inspector/fonts/fonts.css
deleted file mode 100644
index 87d6926169b..00000000000
--- a/devtools/client/inspector/fonts/fonts.css
+++ /dev/null
@@ -1,51 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-.dim > #root,
-.font:not(.has-code) .font-css-code,
-.font-is-local,
-.font-is-remote,
-.font.is-local .font-format-url,
-#template {
-  display: none;
-}
-
-.font.is-remote .font-is-remote,
-.font.is-local .font-is-local {
-  display: inline;
-}
-
-.font-format::before {
-  content: "(";
-}
-
-.font-format::after {
-  content: ")";
-}
-
-.preview-input-toolbar {
-  display: flex;
-  width: 100%;
-}
-
-.font-preview-container {
-  overflow-x: auto;
-}
-
-#preview-text-input {
-  font: inherit;
-  margin-top: 1px;
-  margin-bottom: 1px;
-  padding-top: 0;
-  padding-bottom: 0;
-  flex: 1;
-}
-
-:root {
-  height: 100%;
-}
-
-#root {
-  overflow: auto;
-}
diff --git a/devtools/client/inspector/fonts/fonts.xhtml b/devtools/client/inspector/fonts/fonts.xhtml
index 1aad0ccbb99..373c01a9072 100644
--- a/devtools/client/inspector/fonts/fonts.xhtml
+++ b/devtools/client/inspector/fonts/fonts.xhtml
@@ -11,7 +11,6 @@
   <head>
     <title>&title;</title>
     <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
-    <link rel="stylesheet" href="fonts.css" type="text/css"/>
     <link rel="stylesheet" href="chrome://devtools/skin/common.css" type="text/css"/>
     <link rel="stylesheet" href="chrome://devtools/skin/fonts.css" type="text/css"/>
     <script type="application/javascript;version=1.8" src="chrome://devtools/content/shared/theme-switching.js"/>
diff --git a/devtools/client/inspector/rules/rules.css b/devtools/client/inspector/rules/rules.css
deleted file mode 100644
index 2ea3903ad8b..00000000000
--- a/devtools/client/inspector/rules/rules.css
+++ /dev/null
@@ -1,118 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-
-* {
-  box-sizing: border-box;
-}
-
-:root {
-  height: 100%;
-}
-
-body {
-  margin: 0;
-  display: flex;
-  flex-direction: column;
-  height: 100%;
-}
-
-#ruleview-container {
-  -moz-user-select: text;
-  overflow: auto;
-  min-height: 0;
-  flex: 1;
-}
-
-#ruleview-container.non-interactive {
-  pointer-events: none;
-  visibility: collapse;
-  transition: visibility 0.25s;
-}
-
-.devtools-toolbar {
-  width: 100%;
-  display: flex;
-}
-
-#pseudo-class-panel {
-  position: relative;
-  margin-top: -1px;
-  margin-bottom: -1px;
-  overflow-y: hidden;
-  max-height: 24px;
-  outline: 0 !important;
-  transition-property: max-height;
-  transition-duration: 150ms;
-  transition-timing-function: ease;
-}
-
-#pseudo-class-panel[hidden] {
-  max-height: 0px;
-}
-
-#pseudo-class-panel > label {
-  -moz-user-select: none;
-  flex-grow: 1;
-  display: flex;
-  align-items: center;
-}
-
-.ruleview {
-  overflow: auto;
-  -moz-user-select: text;
-}
-
-.ruleview-code {
-  direction: ltr;
-}
-
-.ruleview-property:not(:hover) > .ruleview-enableproperty {
-  pointer-events: none;
-}
-
-.ruleview-namecontainer {
-  cursor: text;
-}
-
-.ruleview-propertyvaluecontainer {
-  cursor: text;
-  padding-right: 5px;
-}
-
-.ruleview-propertyvaluecontainer a {
-  cursor: pointer;
-}
-
-.ruleview-computedlist,
-.ruleview-overridden-rule-filter[hidden],
-.ruleview-warning[hidden] {
-  display: none;
-}
-
-.ruleview-computedlist[user-open],
-.ruleview-computedlist[filter-open] {
-  display: block;
-}
-
-.ruleview-expandable-container {
-  display: none;
-}
-
-.show-expandable-container + .ruleview-expandable-container {
-  display: block;
-}
-
-.ruleview .ruleview-expander {
-  vertical-align: middle;
-}
-
-.ruleview-header {
-  vertical-align: middle;
-  min-height: 1.5em;
-  line-height: 1.5em;
-}
-
-.ruleview-header.ruleview-expandable-header {
-  cursor: pointer;
-}
diff --git a/devtools/client/inspector/rules/rules.xhtml b/devtools/client/inspector/rules/rules.xhtml
index f864c3eab40..7044916def1 100644
--- a/devtools/client/inspector/rules/rules.xhtml
+++ b/devtools/client/inspector/rules/rules.xhtml
@@ -17,7 +17,6 @@
     <title>&ruleViewTitle;</title>
     <link rel="stylesheet" href="chrome://global/skin/global.css"  type="text/css"/>
     <link rel="stylesheet" href="chrome://devtools/skin/common.css"  type="text/css"/>
-    <link rel="stylesheet" href="chrome://devtools/content/inspector/rules/rules.css"  type="text/css"/>
     <link rel="stylesheet" href="chrome://devtools/skin/rules.css"  type="text/css"/>
     <script type="application/javascript;version=1.8" src="chrome://devtools/content/shared/theme-switching.js"/>
     <script type="application/javascript;version=1.8">
@@ -52,7 +51,7 @@
       </div>
     </div>
 
-    <div id="ruleview-container" class="ruleview devtools-monospace">
+    <div id="ruleview-container" class="devtools-monospace">
     </div>
   </body>
 </html>
diff --git a/devtools/client/jar.mn b/devtools/client/jar.mn
index 03964840121..58a64445a6f 100644
--- a/devtools/client/jar.mn
+++ b/devtools/client/jar.mn
@@ -27,14 +27,12 @@ devtools.jar:
     content/styleeditor/styleeditor.css (styleeditor/styleeditor.css)
     content/storage/storage.xul (storage/storage.xul)
     content/inspector/computed/computed.xhtml (inspector/computed/computed.xhtml)
-    content/inspector/fonts/fonts.css (inspector/fonts/fonts.css)
     content/inspector/fonts/fonts.js (inspector/fonts/fonts.js)
     content/inspector/fonts/fonts.xhtml (inspector/fonts/fonts.xhtml)
     content/inspector/layout/layout.js (inspector/layout/layout.js)
     content/inspector/layout/layout.xhtml (inspector/layout/layout.xhtml)
     content/inspector/markup/markup.css (inspector/markup/markup.css)
     content/inspector/markup/markup.xhtml (inspector/markup/markup.xhtml)
-    content/inspector/rules/rules.css (inspector/rules/rules.css)
     content/inspector/rules/rules.xhtml (inspector/rules/rules.xhtml)
     content/animationinspector/animation-controller.js (animationinspector/animation-controller.js)
     content/animationinspector/animation-panel.js (animationinspector/animation-panel.js)
@@ -148,7 +146,9 @@ devtools.jar:
     content/aboutdebugging/aboutdebugging.css (aboutdebugging/aboutdebugging.css)
     content/aboutdebugging/aboutdebugging.js (aboutdebugging/aboutdebugging.js)
 %   skin devtools classic/1.0 %skin/
-*   skin/common.css (themes/common.css)
+    skin/devtools-browser.css (themes/devtools-browser.css)
+    skin/common.css (themes/common.css)
+    skin/splitters.css (themes/splitters.css)
     skin/dark-theme.css (themes/dark-theme.css)
     skin/light-theme.css (themes/light-theme.css)
     skin/toolbars.css (themes/toolbars.css)
diff --git a/devtools/client/locales/en-US/webConsole.dtd b/devtools/client/locales/en-US/webConsole.dtd
index a2f8b41c231..17ae026992c 100644
--- a/devtools/client/locales/en-US/webConsole.dtd
+++ b/devtools/client/locales/en-US/webConsole.dtd
@@ -11,11 +11,6 @@
 <!ENTITY window.title "Web Console">
 <!ENTITY browserConsole.title "Browser Console">
 
-<!-- LOCALIZATION NOTE (saveBodies.label): You can see this string in the Web
-   - Console context menu. -->
-<!ENTITY saveBodies.label     "Log Request and Response Bodies">
-<!ENTITY saveBodies.accesskey "L">
-
 <!-- LOCALIZATION NOTE (openURL.label): You can see this string in the Web
    - Console context menu. -->
 <!ENTITY openURL.label     "Open URL in New Tab">
diff --git a/devtools/client/netmonitor/har/har-automation.js b/devtools/client/netmonitor/har/har-automation.js
index 112810d0229..665917e1720 100644
--- a/devtools/client/netmonitor/har/har-automation.js
+++ b/devtools/client/netmonitor/har/har-automation.js
@@ -73,11 +73,8 @@ var HarAutomation = Class({
     this.tabClient = this.toolbox.target.activeTab;
     this.webConsoleClient = this.toolbox.target.activeConsole;
 
-    let netPrefs = { "NetworkMonitor.saveRequestAndResponseBodies": true };
-    this.webConsoleClient.setPreferences(netPrefs, () => {
-      this.tabWatcher = new TabWatcher(this.toolbox, this);
-      this.tabWatcher.connect();
-    });
+    this.tabWatcher = new TabWatcher(this.toolbox, this);
+    this.tabWatcher.connect();
   },
 
   pageLoadBegin: function(aResponse) {
diff --git a/devtools/client/netmonitor/netmonitor-controller.js b/devtools/client/netmonitor/netmonitor-controller.js
index f0dfdb03db9..e15ab28063b 100644
--- a/devtools/client/netmonitor/netmonitor-controller.js
+++ b/devtools/client/netmonitor/netmonitor-controller.js
@@ -10,7 +10,6 @@ var { classes: Cc, interfaces: Ci, utils: Cu } = Components;
 const NET_STRINGS_URI = "chrome://devtools/locale/netmonitor.properties";
 const PKI_STRINGS_URI = "chrome://pippki/locale/pippki.properties";
 const LISTENERS = [ "NetworkActivity" ];
-const NET_PREFS = { "NetworkMonitor.saveRequestAndResponseBodies": true };
 
 // The panel's window global is an EventEmitter firing the following events:
 const EVENTS = {
@@ -223,13 +222,6 @@ var NetMonitorController = {
       this.tabClient = this._target.activeTab;
     }
 
-    let connectWebConsole = () => {
-      let deferred = promise.defer();
-      this.webConsoleClient = this._target.activeConsole;
-      this.webConsoleClient.setPreferences(NET_PREFS, deferred.resolve);
-      return deferred.promise;
-    };
-
     let connectTimeline = () => {
       // Don't start up waiting for timeline markers if the server isn't
       // recent enough to emit the markers we're interested in.
@@ -239,7 +231,7 @@ var NetMonitorController = {
       }
     };
 
-    yield connectWebConsole();
+    this.webConsoleClient = this._target.activeConsole;
     yield connectTimeline();
 
     this.TargetEventsHandler.connect();
diff --git a/devtools/client/netmonitor/test/browser.ini b/devtools/client/netmonitor/test/browser.ini
index d3835d8c69d..89c80f005f2 100644
--- a/devtools/client/netmonitor/test/browser.ini
+++ b/devtools/client/netmonitor/test/browser.ini
@@ -74,6 +74,7 @@ skip-if = e10s # Bug 1091596
 [browser_net_html-preview.js]
 [browser_net_icon-preview.js]
 [browser_net_image-tooltip.js]
+skip-if = (os == "win" && os_version == "6.2" && bits == 64) # Bug 1234341
 [browser_net_json-long.js]
 [browser_net_json-malformed.js]
 [browser_net_json_custom_mime.js]
diff --git a/devtools/client/shared/DOMHelpers.jsm b/devtools/client/shared/DOMHelpers.jsm
index 4c2bd522d38..6918ee08f77 100644
--- a/devtools/client/shared/DOMHelpers.jsm
+++ b/devtools/client/shared/DOMHelpers.jsm
@@ -137,7 +137,7 @@ DOMHelpers.prototype = {
    * chrome iframes are loaded in content docshells (in Firefox
    * tabs for example).
    */
-  onceDOMReady: function Helpers_onLocationChange(callback) {
+  onceDOMReady: function Helpers_onLocationChange(callback, targetURL) {
     let window = this.window;
     let docShell = window.QueryInterface(Ci.nsIInterfaceRequestor)
                          .getInterface(Ci.nsIWebNavigation)
@@ -151,6 +151,12 @@ DOMHelpers.prototype = {
         Services.tm.mainThread.dispatch(callback, 0);
       }
     }
-    docShell.chromeEventHandler.addEventListener("DOMContentLoaded", onReady, false);
+    if ((window.document.readyState == "complete" ||
+         window.document.readyState == "interactive") &&
+         window.location.href == targetURL) {
+      Services.tm.mainThread.dispatch(callback, 0);
+    } else {
+      docShell.chromeEventHandler.addEventListener("DOMContentLoaded", onReady, false);
+    }
   }
 };
diff --git a/devtools/client/shared/test/test-actor-registry.js b/devtools/client/shared/test/test-actor-registry.js
index ca91b00e079..bd551d358bf 100644
--- a/devtools/client/shared/test/test-actor-registry.js
+++ b/devtools/client/shared/test/test-actor-registry.js
@@ -82,6 +82,9 @@ exports.getTestActorWithoutToolbox = Task.async(function* (tab) {
   client.connect(deferred.resolve);
   yield deferred.promise;
 
+  // We also need to make sure the test actor is registered on the server.
+  yield registerTestActor(client);
+
   return getTestActor(client, tab);
 });
 
diff --git a/devtools/client/shared/theme-switching.js b/devtools/client/shared/theme-switching.js
index 372467bc506..7cccf76727d 100644
--- a/devtools/client/shared/theme-switching.js
+++ b/devtools/client/shared/theme-switching.js
@@ -5,6 +5,25 @@
 (function() {
   const SCROLLBARS_URL = "chrome://devtools/skin/floating-scrollbars-light.css";
   let documentElement = document.documentElement;
+
+  let os;
+  let platform = navigator.platform;
+  if (platform.startsWith("Win")) {
+    os = "win";
+  } else if (platform.startsWith("Mac")) {
+    os = "mac";
+  } else {
+    os = "linux";
+  }
+
+  documentElement.setAttribute("platform", os);
+
+  // no-theme attributes allows to just est the platform attribute
+  // to have per-platform CSS working correctly.
+  if (documentElement.getAttribute("no-theme") === "true") {
+    return;
+  }
+
   let devtoolsStyleSheets = new WeakMap();
 
   function forceStyle() {
@@ -144,17 +163,6 @@
   const {require} = Components.utils.import("resource://devtools/shared/Loader.jsm", {});
   const StylesheetUtils = require("sdk/stylesheet/utils");
 
-  let os;
-  let platform = navigator.platform;
-  if (platform.startsWith("Win")) {
-    os = "win";
-  } else if (platform.startsWith("Mac")) {
-    os = "mac";
-  } else {
-    os = "linux";
-  }
-  documentElement.setAttribute("platform", os);
-
   if (documentElement.hasAttribute("force-theme")) {
     switchTheme(documentElement.getAttribute("force-theme"));
   } else {
diff --git a/devtools/client/themes/common.css b/devtools/client/themes/common.css
index b298d47858c..00aa99fe9bf 100644
--- a/devtools/client/themes/common.css
+++ b/devtools/client/themes/common.css
@@ -1,66 +1,33 @@
-%if 0
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-%endif
+
+@import url("splitters.css");
 
 :root {
   font: message-box;
-%ifdef XP_MACOSX
+}
+
+:root[platform="mac"] {
   --monospace-font-family: Menlo, monospace;
-%elifdef XP_WIN
+}
+
+:root[platform="win"] {
   --monospace-font-family: Consolas, monospace;
-%else
+}
+
+:root[platform="linux"] {
   --monospace-font-family: monospace;
-%endif
 }
 
 .devtools-monospace {
   font-family: var(--monospace-font-family);
-%if defined(MOZ_WIDGET_GTK) || defined(MOZ_WIDGET_QT)
+}
+
+:root[platform="linux"] .devtools-monospace {
   font-size: 80%;
-%endif
 }
 
-/* Bottom-docked toolbox minimize transition */
-.devtools-toolbox-bottom-iframe {
-  transition: margin-bottom .1s;
-}
-
-/* Splitters */
-.devtools-horizontal-splitter {
-  -moz-appearance: none;
-  background-image: none;
-  background-color: transparent;
-  border: 0;
-  border-bottom: 1px solid rgba(118, 121, 125, .5);
-  min-height: 3px;
-  height: 3px;
-  margin-top: -3px;
-  position: relative;
-}
-
-.devtools-side-splitter {
-  -moz-appearance: none;
-  background-image: none;
-  background-color: transparent;
-  border: 0;
-  -moz-border-end: 1px solid rgba(118, 121, 125, .5);
-  min-width: 3px;
-  width: 3px;
-  -moz-margin-start: -3px;
-  position: relative;
-  cursor: e-resize;
-}
-
-.devtools-horizontal-splitter.disabled,
-.devtools-side-splitter.disabled {
-  pointer-events: none;
-}
-
-.devtools-toolbox-side-iframe {
-  min-width: 465px;
-}
 
 /* Autocomplete Popup */
 /* Dark and light theme */
@@ -71,11 +38,11 @@
   background-color: transparent;
   border-radius: 3px;
   overflow-x: hidden;
-%if defined(MOZ_WIDGET_GTK) || defined(MOZ_WIDGET_QT)
-  max-height: 32rem;
-%else
   max-height: 40rem;
-%endif
+}
+
+:root[platform="linux"] .devtools-autocomplete-popup {
+  max-height: 32rem;
 }
 
 .devtools-autocomplete-listbox {
@@ -248,17 +215,6 @@
   background: transparent;
 }
 
-/* Eyedropper Widget */
-
-.devtools-eyedropper-panel {
-  pointer-events: none;
-  -moz-appearance: none;
-  width: 156px;
-  height: 120px;
-  background-color: transparent;
-  border: none;
-}
-
 /* links to source code, like displaying `myfile.js:45` */
 
 .devtools-source-link {
diff --git a/devtools/client/themes/devtools-browser.css b/devtools/client/themes/devtools-browser.css
new file mode 100644
index 00000000000..b95d914c02e
--- /dev/null
+++ b/devtools/client/themes/devtools-browser.css
@@ -0,0 +1,27 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+@import url("splitters.css");
+
+/* Bottom-docked toolbox minimize transition */
+.devtools-toolbox-bottom-iframe {
+  transition: margin-bottom .1s;
+}
+
+.devtools-toolbox-side-iframe {
+  min-width: 465px;
+}
+
+/* Eyedropper Widget */
+/* <panel> added to mainPopupSet */
+
+.devtools-eyedropper-panel {
+  pointer-events: none;
+  -moz-appearance: none;
+  width: 156px;
+  height: 120px;
+  background-color: transparent;
+  border: none;
+}
+
diff --git a/devtools/client/themes/fonts.css b/devtools/client/themes/fonts.css
index 2c4a36534c2..7f847c66487 100644
--- a/devtools/client/themes/fonts.css
+++ b/devtools/client/themes/fonts.css
@@ -1,7 +1,15 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
 * {
   box-sizing: border-box;
 }
 
+:root {
+  height: 100%;
+}
+
 body {
   display: flex;
   flex-direction: column;
@@ -10,6 +18,10 @@ body {
   padding-bottom: 20px;
 }
 
+#root {
+  overflow: auto;
+}
+
 #all-fonts {
   padding: 0;
   margin: 0;
@@ -25,6 +37,46 @@ body {
   right: 0;
 }
 
+.dim > #root,
+.font:not(.has-code) .font-css-code,
+.font-is-local,
+.font-is-remote,
+.font.is-local .font-format-url,
+#template {
+  display: none;
+}
+
+.font.is-remote .font-is-remote,
+.font.is-local .font-is-local {
+  display: inline;
+}
+
+.font-format::before {
+  content: "(";
+}
+
+.font-format::after {
+  content: ")";
+}
+
+.preview-input-toolbar {
+  display: flex;
+  width: 100%;
+}
+
+.font-preview-container {
+  overflow-x: auto;
+}
+
+#preview-text-input {
+  font: inherit;
+  margin-top: 1px;
+  margin-bottom: 1px;
+  padding-top: 0;
+  padding-bottom: 0;
+  flex: 1;
+}
+
 .font {
   padding: 10px 10px;
 }
diff --git a/devtools/client/themes/inspector.css b/devtools/client/themes/inspector.css
index e27e148612a..614affa0527 100644
--- a/devtools/client/themes/inspector.css
+++ b/devtools/client/themes/inspector.css
@@ -72,6 +72,14 @@
   cursor: pointer;
 }
 
+.event-header:first-child {
+  border-width: 0;
+}
+
+.event-header:not(:first-child) {
+  border-width: 1px 0 0 0;
+}
+
 .event-tooltip-event-type,
 .event-tooltip-filename,
 .event-tooltip-attributes {
@@ -105,8 +113,15 @@
 
 .event-tooltip-content-box {
   display: none;
-  overflow: auto;
+  height: 100px;
+  overflow: hidden;
   -moz-margin-end: 0;
+  border: 1px solid var(--theme-splitter-color);
+  border-width: 1px 0 0 0;
+}
+
+.event-toolbox-content-box iframe {
+  height: 100%;
 }
 
 .event-tooltip-content-box[open] {
diff --git a/devtools/client/themes/rules.css b/devtools/client/themes/rules.css
index d57e7002442..6e171f5e1bb 100644
--- a/devtools/client/themes/rules.css
+++ b/devtools/client/themes/rules.css
@@ -13,10 +13,103 @@
   --rule-filter-icon: url(images/magnifying-glass.png);
 }
 
-.ruleview {
+* {
+  box-sizing: border-box;
+}
+
+:root {
   height: 100%;
 }
 
+body {
+  margin: 0;
+  display: flex;
+  flex-direction: column;
+  height: 100%;
+}
+
+#ruleview-container {
+  -moz-user-select: text;
+  overflow: auto;
+  min-height: 0;
+  flex: 1;
+  height: 100%;
+}
+
+#ruleview-container.non-interactive {
+  pointer-events: none;
+  visibility: collapse;
+  transition: visibility 0.25s;
+}
+
+.devtools-toolbar {
+  width: 100%;
+  display: flex;
+}
+
+#pseudo-class-panel {
+  position: relative;
+  margin-top: -1px;
+  margin-bottom: -1px;
+  overflow-y: hidden;
+  max-height: 24px;
+  outline: 0 !important;
+  transition-property: max-height;
+  transition-duration: 150ms;
+  transition-timing-function: ease;
+}
+
+#pseudo-class-panel[hidden] {
+  max-height: 0px;
+}
+
+#pseudo-class-panel > label {
+  -moz-user-select: none;
+  flex-grow: 1;
+  display: flex;
+  align-items: center;
+}
+
+.ruleview-code {
+  direction: ltr;
+}
+
+.ruleview-property:not(:hover) > .ruleview-enableproperty {
+  pointer-events: none;
+}
+
+.ruleview-expandable-container {
+  display: none;
+}
+
+.show-expandable-container + .ruleview-expandable-container {
+  display: block;
+}
+
+.ruleview-namecontainer {
+  cursor: text;
+}
+
+.ruleview-propertyvaluecontainer {
+  cursor: text;
+  padding-right: 5px;
+}
+
+.ruleview-propertyvaluecontainer a {
+  cursor: pointer;
+}
+
+.ruleview-computedlist,
+.ruleview-overridden-rule-filter[hidden],
+.ruleview-warning[hidden] {
+  display: none;
+}
+
+.ruleview-computedlist[user-open],
+.ruleview-computedlist[filter-open] {
+  display: block;
+}
+
 .ruleview-rule-source {
   text-align: end;
   float: right;
@@ -46,6 +139,9 @@
   padding: 1px 4px;
   -moz-user-select: none;
   word-wrap: break-word;
+  vertical-align: middle;
+  min-height: 1.5em;
+  line-height: 1.5em;
 }
 
 :root[platform="win"] .ruleview-header,
@@ -53,6 +149,10 @@
   margin-top: 4px;
 }
 
+.ruleview-header.ruleview-expandable-header {
+  cursor: pointer;
+}
+
 .ruleview-rule-pseudo-element {
   padding-left:20px;
   border-left: solid 10px;
@@ -148,6 +248,7 @@
 }
 
 .ruleview-expander {
+  vertical-align: middle;
   display: inline-block;
 }
 
diff --git a/devtools/client/themes/splitters.css b/devtools/client/themes/splitters.css
new file mode 100644
index 00000000000..c71218625d5
--- /dev/null
+++ b/devtools/client/themes/splitters.css
@@ -0,0 +1,34 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* Splitters */
+.devtools-horizontal-splitter {
+  -moz-appearance: none;
+  background-image: none;
+  background-color: transparent;
+  border: 0;
+  border-bottom: 1px solid rgba(118, 121, 125, .5);
+  min-height: 3px;
+  height: 3px;
+  margin-top: -3px;
+  position: relative;
+}
+
+.devtools-side-splitter {
+  -moz-appearance: none;
+  background-image: none;
+  background-color: transparent;
+  border: 0;
+  -moz-border-end: 1px solid rgba(118, 121, 125, .5);
+  min-width: 3px;
+  width: 3px;
+  -moz-margin-start: -3px;
+  position: relative;
+  cursor: e-resize;
+}
+
+.devtools-horizontal-splitter.disabled,
+.devtools-side-splitter.disabled {
+  pointer-events: none;
+}
diff --git a/devtools/client/webconsole/test/browser.ini b/devtools/client/webconsole/test/browser.ini
index 88c9125322b..fb173e5bfbb 100644
--- a/devtools/client/webconsole/test/browser.ini
+++ b/devtools/client/webconsole/test/browser.ini
@@ -171,6 +171,7 @@ skip-if = buildapp == 'mulet' || e10s # Bug 1042253 - webconsole e10s tests
 [browser_console_log_inspectable_object.js]
 [browser_console_native_getters.js]
 [browser_console_navigation_marker.js]
+[browser_console_netlogging.js]
 [browser_console_nsiconsolemessage.js]
 skip-if = buildapp == 'mulet'
 [browser_console_optimized_out_vars.js]
@@ -300,7 +301,6 @@ skip-if = os != "mac"
 [browser_webconsole_bug_817834_add_edited_input_to_history.js]
 [browser_webconsole_bug_837351_securityerrors.js]
 skip-if = buildapp == 'mulet'
-[browser_webconsole_bug_915141_toggle_response_logging_with_keyboard.js]
 [browser_webconsole_filter_buttons_contextmenu.js]
 [browser_webconsole_bug_1006027_message_timestamps_incorrect.js]
 skip-if = e10s # Bug 1042253 - webconsole e10s tests (Linux debug intermittent)
diff --git a/devtools/client/webconsole/test/browser_console_netlogging.js b/devtools/client/webconsole/test/browser_console_netlogging.js
new file mode 100644
index 00000000000..50e0fd3d845
--- /dev/null
+++ b/devtools/client/webconsole/test/browser_console_netlogging.js
@@ -0,0 +1,50 @@
+/* vim:set ts=2 sw=2 sts=2 et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Tests that network log messages bring up the network panel.
+
+"use strict";
+
+const TEST_URI = "data:text/html;charset=utf-8,Web Console network " +
+                 "logging tests";
+
+const TEST_NETWORK_REQUEST_URI =
+  "http://example.com/browser/devtools/client/webconsole/test/" +
+  "test-network-request.html";
+
+var hud;
+
+function test() {
+  loadTab(TEST_URI).then((tab) => {
+    HUDService.openBrowserConsoleOrFocus().then(aHud => {
+      hud = aHud;
+      HUDService.lastFinishedRequest.callback = testResponse;
+      BrowserTestUtils.loadURI(gBrowser.selectedBrowser,
+                               TEST_NETWORK_REQUEST_URI);
+    });
+  });
+}
+
+function testResponse(request) {
+  hud.ui.webConsoleClient.getResponseContent(request.actor,
+    function(contentPacket) {
+      hud.ui.webConsoleClient.getRequestPostData(request.actor,
+        function(postDataPacket) {
+          // Check if page load was logged correctly.
+          ok(request, "Page load was logged");
+
+          is(request.request.url, TEST_NETWORK_REQUEST_URI,
+            "Logged network entry is page load");
+          is(request.request.method, "GET", "Method is correct");
+          ok(!postDataPacket.postData.text, "No request body was stored");
+          ok(postDataPacket.postDataDiscarded, "Request body was discarded");
+          ok(!contentPacket.content.text, "No response body was stored");
+          ok(contentPacket.contentDiscarded || request.fromCache,
+             "Response body was discarded or response came from the cache");
+
+          executeSoon(finishTest);
+        });
+    });
+}
diff --git a/devtools/client/webconsole/test/browser_webconsole_bug_600183_charset.js b/devtools/client/webconsole/test/browser_webconsole_bug_600183_charset.js
index 392831d51d4..c0880b12228 100644
--- a/devtools/client/webconsole/test/browser_webconsole_bug_600183_charset.js
+++ b/devtools/client/webconsole/test/browser_webconsole_bug_600183_charset.js
@@ -54,11 +54,6 @@ add_task(function* () {
 
   let hud = yield openConsole();
 
-  yield hud.ui.setSaveRequestAndResponseBodies(true);
-
-  ok(hud.ui._saveRequestAndResponseBodies,
-    "The saveRequestAndResponseBodies property was successfully set.");
-
   let gotLastRequest = waitForRequest();
 
   let loaded = loadBrowser(browser);
diff --git a/devtools/client/webconsole/test/browser_webconsole_bug_630733_response_redirect_headers.js b/devtools/client/webconsole/test/browser_webconsole_bug_630733_response_redirect_headers.js
index 4821372b646..c29be251c3a 100644
--- a/devtools/client/webconsole/test/browser_webconsole_bug_630733_response_redirect_headers.js
+++ b/devtools/client/webconsole/test/browser_webconsole_bug_630733_response_redirect_headers.js
@@ -33,20 +33,15 @@ function consoleOpened(hud) {
   let deferred = promise.defer();
 
   webConsoleClient = hud.ui.webConsoleClient;
-  hud.ui.setSaveRequestAndResponseBodies(true).then(() => {
-    ok(hud.ui._saveRequestAndResponseBodies,
-      "The saveRequestAndResponseBodies property was successfully set.");
-
-    HUDService.lastFinishedRequest.callback = (aHttpRequest) => {
-      let status = aHttpRequest.response.status;
-      lastFinishedRequests[status] = aHttpRequest;
-      if ("301" in lastFinishedRequests &&
-          "404" in lastFinishedRequests) {
-        deferred.resolve();
-      }
-    };
-    content.location = TEST_URI2;
-  });
+  HUDService.lastFinishedRequest.callback = (aHttpRequest) => {
+    let status = aHttpRequest.response.status;
+    lastFinishedRequests[status] = aHttpRequest;
+    if ("301" in lastFinishedRequests &&
+        "404" in lastFinishedRequests) {
+      deferred.resolve();
+    }
+  };
+  content.location = TEST_URI2;
 
   return deferred.promise;
 }
diff --git a/devtools/client/webconsole/test/browser_webconsole_bug_915141_toggle_response_logging_with_keyboard.js b/devtools/client/webconsole/test/browser_webconsole_bug_915141_toggle_response_logging_with_keyboard.js
deleted file mode 100644
index dfb2aff53b4..00000000000
--- a/devtools/client/webconsole/test/browser_webconsole_bug_915141_toggle_response_logging_with_keyboard.js
+++ /dev/null
@@ -1,124 +0,0 @@
-/* vim:set ts=2 sw=2 sts=2 et: */
-/*
- * Any copyright is dedicated to the Public Domain.
- * http://creativecommons.org/publicdomain/zero/1.0/
- */
-
-// Tests that the 'Log Request and Response Bodies' buttons can be toggled
-// with keyboard.
-
-"use strict";
-
-const TEST_URI = "data:text/html;charset=utf-8,Web Console test for " +
-                 "bug 915141: Toggle log response bodies with keyboard";
-var hud;
-
-function test() {
-  let saveBodiesMenuItem;
-  let saveBodiesContextMenuItem;
-
-  loadTab(TEST_URI).then(({tab: tab}) => {
-    return openConsole(tab);
-  })
-  .then((aHud) => {
-    hud = aHud;
-    saveBodiesMenuItem = hud.ui.rootElement.querySelector("#saveBodies");
-    saveBodiesContextMenuItem = hud.ui.rootElement.querySelector("#saveBodiesContextMenu");
-
-    // Test the context menu action.
-    info("Testing 'Log Request and Response Bodies' menuitem of right click " +
-         "context menu.");
-
-    return openPopup(saveBodiesContextMenuItem);
-  })
-  .then(() => {
-    is(saveBodiesContextMenuItem.getAttribute("checked"), "false",
-       "Context menu: 'log responses' is not checked before action.");
-    is(hud.ui._saveRequestAndResponseBodies, false,
-       "Context menu: Responses are not logged before action.");
-
-    EventUtils.synthesizeKey("VK_DOWN", {});
-    EventUtils.synthesizeKey("VK_RETURN", {});
-
-    return waitForUpdate(saveBodiesContextMenuItem);
-  })
-  .then(() => {
-    is(saveBodiesContextMenuItem.getAttribute("checked"), "true",
-       "Context menu: 'log responses' is checked after menuitem was selected " +
-       "with keyboard.");
-    is(hud.ui._saveRequestAndResponseBodies, true,
-       "Context menu: Responses are saved after menuitem was selected with " +
-       "keyboard.");
-
-    return openPopup(saveBodiesMenuItem);
-  })
-  .then(() => {
-    // Test the 'Net' menu item.
-    info("Testing 'Log Request and Response Bodies' menuitem of 'Net' menu " +
-         "in the console.");
-    // 'Log Request and Response Bodies' should be selected due to previous
-    // test.
-
-    is(saveBodiesMenuItem.getAttribute("checked"), "true",
-       "Console net menu: 'log responses' is checked before action.");
-    is(hud.ui._saveRequestAndResponseBodies, true,
-       "Console net menu: Responses are logged before action.");
-
-    // The correct item is the last one in the menu.
-    EventUtils.synthesizeKey("VK_UP", {});
-    EventUtils.synthesizeKey("VK_RETURN", {});
-
-    return waitForUpdate(saveBodiesMenuItem);
-  })
-  .then(() => {
-    is(saveBodiesMenuItem.getAttribute("checked"), "false",
-       "Console net menu: 'log responses' is NOT checked after menuitem was " +
-       "selected with keyboard.");
-    is(hud.ui._saveRequestAndResponseBodies, false,
-       "Responses are NOT saved after menuitem was selected with keyboard.");
-    hud = null;
-  })
-  .then(finishTest);
-}
-
-/**
- * Opens and waits for the menu containing menuItem to open.
- * @param menuItem MenuItem
- *        A MenuItem in a menu that should be opened.
- * @return A promise that's resolved once menu is open.
- */
-function openPopup(menuItem) {
-  let menu = menuItem.parentNode;
-
-  let menuOpened = promise.defer();
-  let uiUpdated = promise.defer();
-  // The checkbox menuitem is updated asynchronously on 'popupshowing' event so
-  // it's better to wait for both the update to happen and the menu to open
-  // before continuing or the test might fail due to a race between menu being
-  // shown and the item updated to have the correct state.
-  hud.ui.once("save-bodies-ui-toggled", uiUpdated.resolve);
-  menu.addEventListener("popupshown", function onPopup() {
-    menu.removeEventListener("popupshown", onPopup);
-    menuOpened.resolve();
-  });
-
-  menu.openPopup();
-  return Promise.all([menuOpened.promise, uiUpdated.promise]);
-}
-
-/**
- * Waits for the settings and menu containing menuItem to update.
- * @param menuItem MenuItem
- *        The menuitem that should be updated.
- * @return A promise that's resolved once the settings and menus are updated.
- */
-function waitForUpdate(menuItem) {
-  info("Waiting for settings update to complete.");
-  let deferred = promise.defer();
-  hud.ui.once("save-bodies-pref-reversed", function() {
-    hud.ui.once("save-bodies-ui-toggled", deferred.resolve);
-    // The checked state is only updated once the popup is shown.
-    menuItem.parentNode.openPopup();
-  });
-  return deferred.promise;
-}
diff --git a/devtools/client/webconsole/test/browser_webconsole_netlogging.js b/devtools/client/webconsole/test/browser_webconsole_netlogging.js
index 42feaf3adcd..f304f44931b 100644
--- a/devtools/client/webconsole/test/browser_webconsole_netlogging.js
+++ b/devtools/client/webconsole/test/browser_webconsole_netlogging.js
@@ -74,58 +74,16 @@ function testPageLoad() {
       "Logged network entry is page load");
     is(lastRequest.request.method, "GET", "Method is correct");
     ok(!lastRequest.request.postData.text, "No request body was stored");
-    ok(lastRequest.discardRequestBody, "Request body was discarded");
-    ok(!lastRequest.response.content.text, "No response body was stored");
-    ok(lastRequest.discardResponseBody || lastRequest.fromCache,
-       "Response body was discarded or response came from the cache");
-
-    lastRequest = null;
-    requestCallback = null;
-    executeSoon(testPageLoadBody);
-  };
-
-  content.location = TEST_NETWORK_REQUEST_URI;
-}
-
-function testPageLoadBody() {
-  // Turn on logging of request bodies and check again.
-  hud.ui.setSaveRequestAndResponseBodies(true).then(() => {
-    ok(hud.ui._saveRequestAndResponseBodies,
-      "The saveRequestAndResponseBodies property was successfully set.");
-
-    testPageLoadBodyAfterSettingUpdate();
-  });
-}
-
-function testPageLoadBodyAfterSettingUpdate() {
-  let loaded = false;
-  let requestCallbackInvoked = false;
-
-  requestCallback = function() {
-    ok(lastRequest, "Page load was logged again");
-    ok(!lastRequest.discardResponseBody, "Response body was not discarded");
+    ok(!lastRequest.discardRequestBody, "Request body was not discarded");
     is(lastRequest.response.content.text.indexOf("<!DOCTYPE HTML>"), 0,
       "Response body's beginning is okay");
 
     lastRequest = null;
     requestCallback = null;
-    requestCallbackInvoked = true;
-
-    if (loaded) {
-      executeSoon(testXhrGet);
-    }
+    executeSoon(testXhrGet);
   };
 
-  browser.addEventListener("load", function onLoad() {
-    browser.removeEventListener("load", onLoad, true);
-    loaded = true;
-
-    if (requestCallbackInvoked) {
-      executeSoon(testXhrGet);
-    }
-  }, true);
-
-  content.location.reload();
+  content.location = TEST_NETWORK_REQUEST_URI;
 }
 
 function testXhrGet() {
diff --git a/devtools/client/webconsole/webconsole.js b/devtools/client/webconsole/webconsole.js
index a3ee06710ac..b3ddc3094ad 100644
--- a/devtools/client/webconsole/webconsole.js
+++ b/devtools/client/webconsole/webconsole.js
@@ -367,42 +367,13 @@ WebConsoleFrame.prototype = {
 
   _destroyer: null,
 
-  // Used in tests.
-  _saveRequestAndResponseBodies: false,
+  _saveRequestAndResponseBodies: true,
 
   // Chevron width at the starting of Web Console's input box.
   _chevronWidth: 0,
   // Width of the monospace characters in Web Console's input box.
   _inputCharWidth: 0,
 
-  /**
-   * Tells whether to save the bodies of network requests and responses.
-   * Disabled by default to save memory.
-   *
-   * @return boolean
-   *         The saveRequestAndResponseBodies pref value.
-   */
-  getSaveRequestAndResponseBodies:
-  function WCF_getSaveRequestAndResponseBodies() {
-    let deferred = promise.defer();
-    let toGet = [
-      "NetworkMonitor.saveRequestAndResponseBodies"
-    ];
-
-    // Make sure the web console client connection is established first.
-    this.webConsoleClient.getPreferences(toGet, response => {
-      if (!response.error) {
-        this._saveRequestAndResponseBodies = response.preferences[toGet[0]];
-        deferred.resolve(this._saveRequestAndResponseBodies);
-      }
-      else {
-        deferred.reject(response.error);
-      }
-    });
-
-    return deferred.promise;
-  },
-
   /**
    * Setter for saving of network request and response bodies.
    *
@@ -560,47 +531,6 @@ WebConsoleFrame.prototype = {
     // calculations.
     this._updateCharSize();
 
-    let updateSaveBodiesPrefUI = (element) => {
-      this.getSaveRequestAndResponseBodies().then(value => {
-        element.setAttribute("checked", value);
-        this.emit("save-bodies-ui-toggled");
-      });
-    }
-
-    let reverseSaveBodiesPref = ({ target: element }) => {
-      this.getSaveRequestAndResponseBodies().then(value => {
-        this.setSaveRequestAndResponseBodies(!value);
-        element.setAttribute("checked", value);
-        this.emit("save-bodies-pref-reversed");
-      });
-    }
-
-    let saveBodiesDisabled = !this.getFilterState("networkinfo") &&
-                             !this.getFilterState("netxhr") &&
-                             !this.getFilterState("network");
-
-    let saveBodies = doc.getElementById("saveBodies");
-    saveBodies.addEventListener("command", reverseSaveBodiesPref);
-    saveBodies.disabled = saveBodiesDisabled;
-
-    let saveBodiesContextMenu = doc.getElementById("saveBodiesContextMenu");
-    saveBodiesContextMenu.addEventListener("command", reverseSaveBodiesPref);
-    saveBodiesContextMenu.disabled = saveBodiesDisabled;
-
-    saveBodies.parentNode.addEventListener("popupshowing", () => {
-      updateSaveBodiesPrefUI(saveBodies);
-      saveBodies.disabled = !this.getFilterState("networkinfo") &&
-                            !this.getFilterState("netxhr") &&
-                            !this.getFilterState("network");
-    });
-
-    saveBodiesContextMenu.parentNode.addEventListener("popupshowing", () => {
-      updateSaveBodiesPrefUI(saveBodiesContextMenu);
-      saveBodiesContextMenu.disabled = !this.getFilterState("networkinfo") &&
-                                       !this.getFilterState("netxhr") &&
-                                       !this.getFilterState("network");
-    });
-
     let clearButton = doc.getElementsByClassName("webconsole-clear-console-button")[0];
     clearButton.addEventListener("command", () => {
       this.owner._onClearButton();
@@ -951,15 +881,6 @@ WebConsoleFrame.prototype = {
         let prefKey = target.getAttribute("prefKey");
         this.setFilterState(prefKey, state);
 
-        // Disable the log response and request body if network logging is off.
-        if (prefKey == "networkinfo" || prefKey == "netxhr" || prefKey == "network") {
-          let checkState = !this.getFilterState("networkinfo") &&
-                           !this.getFilterState("netxhr") &&
-                           !this.getFilterState("network");
-          this.document.getElementById("saveBodies").disabled = checkState;
-          this.document.getElementById("saveBodiesContextMenu").disabled = checkState;
-        }
-
         // Adjust the state of the button appropriately.
         let menuPopup = target.parentNode;
 
@@ -5089,8 +5010,13 @@ WebConsoleConnectionProxy.prototype = {
     }
 
     this.webConsoleClient = webConsoleClient;
-
     this._hasNativeConsoleAPI = response.nativeConsoleAPI;
+
+    // There is no way to view response bodies from the Browser Console, so do
+    // not waste the memory.
+    let saveBodies = !this.webConsoleFrame.owner._browserConsole;
+    this.webConsoleFrame.setSaveRequestAndResponseBodies(saveBodies);
+
     this.webConsoleClient.on("networkEvent", this._onNetworkEvent);
     this.webConsoleClient.on("networkEventUpdate", this._onNetworkEventUpdate);
 
diff --git a/devtools/client/webconsole/webconsole.xul b/devtools/client/webconsole/webconsole.xul
index e7052f5b98b..b7d96516d14 100644
--- a/devtools/client/webconsole/webconsole.xul
+++ b/devtools/client/webconsole/webconsole.xul
@@ -72,8 +72,6 @@ function goUpdateConsoleCommands() {
 
   <popupset id="mainPopupSet">
     <menupopup id="output-contextmenu" onpopupshowing="goUpdateGlobalEditMenuItems()">
-      <menuitem id="saveBodiesContextMenu" type="checkbox" label="&saveBodies.label;"
-                accesskey="&saveBodies.accesskey;"/>
       <menuitem id="menu_openURL" label="&openURL.label;"
                 accesskey="&openURL.accesskey;" command="consoleCmd_openURL"
                 selection="network" selectionType="single"/>
@@ -110,9 +108,6 @@ function goUpdateConsoleCommands() {
                         prefKey="netxhr"/>
               <menuitem label="&btnConsoleLog;" type="checkbox" autocheck="false"
                         prefKey="networkinfo"/>
-              <menuseparator id="saveBodiesSeparator" />
-              <menuitem id="saveBodies" type="checkbox" label="&saveBodies.label;"
-                        accesskey="&saveBodies.accesskey;"/>
             </menupopup>
           </toolbarbutton>
           <toolbarbutton label="&btnPageCSS.label;" type="menu-button"
diff --git a/devtools/docs/memory-panel.md b/devtools/docs/memory-panel.md
new file mode 100644
index 00000000000..5980691aadc
--- /dev/null
+++ b/devtools/docs/memory-panel.md
@@ -0,0 +1,201 @@
+# Memory Tool Architecture
+
+The memory tool is built of three main elements:
+
+1. `JS::ubi::Node` provides an interface to either the live heap graph, or a
+   serialized, offline snapshot of some heap graph from a previous moment in
+   time. Our various heap analyses (census, dominator trees, shortest paths,
+   etc) run on top of `JS::ubi::Node` graphs.
+
+2. The `HeapAnalysesWorker` runs in a worker thread, performing analyses on
+   snapshots and translating the results into something the frontend can render
+   simply and quickly.
+
+3. Finally, the last element is the frontend that renders data received from the
+   `HeapAnalysesClient` to the DOM and translates user input into requests for
+   new data with the `HeapAnalysesClient`.
+
+Unlike other tools (such as the JavaScript debugger), the memory tool makes very
+little use of the Remote Debugger Server and the actors that reside in it. Use
+of the [`MemoryActor`](devtools/server/actors/memory.js) is limited to toggling
+allocation stack recording on and off, and transferring heap snapshots from the
+debuggee (which is on the server) to the `HeapAnalysesWorker` (which is on the
+client). A nice benefit that naturally emerges, is that supporting "legacy"
+servers (eg, using Firefox Developer Edition as a client to remote debug a
+release Firefox for Android server) is a no-op. As we add new analyses, we can
+run them on snapshots taken on old servers no problem. The only requirement is
+that changes to the snapshot format itself remain backwards compatible.
+
+## `JS::ubi::Node`
+
+`JS::ubi::Node` itself is very well documented in the `js/public/UbiNode.h`
+header. I suggest you at least skim that documentation before continuing.
+
+A "heap snapshot" is a representation of the heap graph at some particular past
+instance in time.
+
+A "heap analysis" is an algorithm that runs on a `JS::ubi::Node` heap
+graph. That's it. Generally, analyses can run on either the live heap graph or a
+deserialized snapshot. Example analyses include "census", which aggregates and
+counts nodes into various user-specified buckets; "dominator trees", which
+compute the "dominates" relation and retained size for all nodes in the heap
+graph; and "shortest paths" which finds the shortest paths from the GC roots to
+some subset of nodes.
+
+### Saving Heap Snapshots
+
+Saving a heap snapshot has a few requirements:
+
+1. The binary format must remain backwards compatible and future extensible.
+
+2. The live heap graph must not mutate while we are in the process of
+   serializing it.
+
+3. The act of saving a heap snapshot should impose as little memory overhead as
+   possible. If we are taking a snapshot to debug frequent out-of-memory errors,
+   we don't want to trigger an OOM ourselves!
+
+To solve (1), we use the protobuf message format. The message definitions
+themselves are in `devtools/shared/heapsnapshot/CoreDump.proto`. We always use
+`optional` fields so we can change our mind about what fields are required
+sometime in the future. Deserialization checks the semantic integrity of
+deserialized protobuf messages.
+
+For (2), we rely on SpiderMonkey's GC rooting hazard static analysis and the
+`AutoCheckCannotGC` dynamic analysis to ensure that neither JS nor GC runs and
+modifies objects or moves them from one address in memory to another. There is
+no equivalent suppression and static analysis technique for the
+[cycle collector](https://developer.mozilla.org/en/docs/Interfacing_with_the_XPCOM_cycle_collector),
+so care must be taken not to invoke methods that could start cycle collection or
+mutate the heap graph from the cycle collector's perspective. At the time of
+writing, we don't yet support saving the cycle collector's portion of the heap
+graph in snapshots, but that work is deemed Very Important and Very High
+Priority.
+
+Finally, (3) imposes upon us that we do not build the serialized heap snapshot
+binary blob in memory, but instead stream it out to disk while generating it.
+
+Once all of that is accounted for, saving snapshots becomes pretty straight
+forward. We traverse the live heap graph with `JS::ubi::Node` and
+`JS::ubi::BreadthFirst`, create a protobuf message for each node and each node's
+edges, and write these messages to disk before continuing the traversal to the
+next node.
+
+This functionality is exposed to chrome JavaScript as the
+`[ThreadSafe]ChromeUtils.saveHeapSnapshot` function. See
+`dom/webidl/ThreadSafeChromeUtils.webidl` for API documentation.
+
+### Reading Heap Snapshots
+
+Reading heap snapshots has less restrictions than saving heap snapshots. The
+protobuf messages that make up the core dump are deserialized one by one, stored
+as a set of `DeserializedNode`s and a set of `DeserializedEdge`s, and the result
+is a `HeapSnapshot` instance.
+
+The `DeserializedNode` and `DeserializedEdge` classes implement the
+`JS::ubi::Node` interface. Analyses running on offline heap snapshots rather
+than the live heap graph operate on these classes (unknowingly, of course).
+
+For more details, see the
+[`mozilla::devtools::HeapSnapshot`](devtools/shared/heapsnapshot/HeapSnapshot.cpp)
+and
+[`mozilla::devtools::Deserialized{Node,Edge}`](devtools/shared/heapsnapshot/DeserializedNode.h)
+classes.
+
+### Heap Analyses
+
+Heap analyses operate on `JS::ubi::Node` graphs without knowledge of whether
+that graph is backed by the live heap graph or an offline heap snapshot. They
+must make sure never to allocate GC things or modify the live heap graph.
+
+In general, analyses are implemented in their own `js/public/UbiFooBar.h` header
+(eg `js/public/UbiCensus.h`), and are exposed to chrome JavaScript code via a
+method on the [`HeapSnapshot`](dom/webidl/HeapSnapshot.webidl) webidl
+interface.
+
+For each analysis we expose to chrome JavaScript on the `HeapSnapshot` webidl
+interface, there is a small amount of glue code in Gecko. The
+[`mozilla::devtools::HeapSnapshot`](devtools/shared/heapsnapshot/HeapSnapshot.h)
+C++ class implements the webidl interface. The analyses methods (eg
+`ComputeDominatorTree`) take the deserialized nodes and edges from the heap
+snapshot, create `JS::ubi::Node`s from them, call the analyses from
+`js/public/Ubi*.h`, and wrap the results in something that can be represented in
+JavaScript.
+
+For API documentation on running specific analyses, see the
+[`HeapSnapshot`](dom/webidl/HeapSnapshot.webidl) webidl interface.
+
+### Testing `JS::ubi::Node`, Snapshots, and Analyses
+
+The majority of the tests reside within `devtools/shared/heapsnapshot/tests/**`.
+For reading and saving heap snapshots, most tests are gtests. The gtests can be
+run with the `mach gtest DevTools.*` command. The rest are integration sanity
+tests to make sure we can read and save snapshots in various environments, such
+as xpcshell or workers. These can be run with the usual `mach test $PATH`
+commands.
+
+There are also `JS::ubi::Node` related unit tests in
+`js/src/jit-test/tests/heap-analysis/*`, `js/src/jit-test/tests/debug/Memory-*`,
+and `js/src/jsapi-tests/testUbiNode.cpp`. See
+https://developer.mozilla.org/en-US/docs/Mozilla/Projects/SpiderMonkey/Running_Automated_JavaScript_Tests#Running_jit-tests
+for running the JIT tests.
+
+## `HeapAnalysesWorker`
+
+The `HeapAnalysesWorker` orchestrates running specific analyses on snapshots and
+transforming the results into something that can simply and quickly be rendered
+by the frontend. The analyses can take some time to run (sometimes on the order
+of seconds), so doing them in a worker thread allows the interface to stay
+responsive. The `HeapAnalysisClient` provides the main thread's interface to the
+worker.
+
+The `HeapAnalysesWorker` doesn't actually do much itself; mostly just shuffling
+data and transforming it from one representation to another or calling utility
+functions that do those things. Most of these are implemented as traversals of
+the resulting census or dominator trees.
+
+See the
+`devtools/shared/heapsnapshot/{CensusUtils,CensusTreeNode,DominatorTreeNode}.js`
+files for details on the various data transformations and shuffling that the
+`HeapAnalysesWorker` delegates to.
+
+### Testing the `HeapAnalysesWorker` and `HeapAnalysesClient`
+
+Tests for the `HeapAnalysesWorker` and `HeapAnalysesClient` reside in
+`devtools/shared/heapsnapshot/tests/**` and can be run with the usual `mach test
+$PATH` command.
+
+## Frontend
+
+The frontend of the memory tool is built with React and Redux.
+
+[React has thorough documentation.](https://facebook.github.io/react/)
+
+[Redux has thorough documentation.](http://rackt.org/redux/index.html)
+
+We have React components in `devtools/client/memory/components/*`.
+
+We have Redux reducers in `devtools/client/memory/reducers/*`.
+
+We have Redux actions and action-creating tasks in
+`devtools/client/memory/actions/*`.
+
+React components should be pure functions from their props to the rendered
+(virtual) DOM. Redux reducers should also be observably pure.
+
+Impurity within the frontend is confined to the tasks that are creating and
+dispatching actions. All communication with the outside world (such as the
+`HeapAnalysesWorker`, the Remote Debugger Server, or the file system) is
+restricted to within these tasks.
+
+### Testing the Frontend
+
+Unit tests for React components are in `devtools/client/memory/test/chrome/*`.
+
+Unit tests for actions, reducers, and state changes are in
+`devtools/client/memory/test/unit/*`.
+
+Holistic integration tests for the frontend and the whole memory tool are in
+`devtools/client/memory/test/browser/*`.
+
+All tests can be run with the usual `mach test $PATH` command.
diff --git a/devtools/shared/Parser.jsm b/devtools/shared/Parser.jsm
index bd3d1736057..b4131f110c1 100644
--- a/devtools/shared/Parser.jsm
+++ b/devtools/shared/Parser.jsm
@@ -46,7 +46,7 @@ Parser.prototype = {
     // all the scripts. Fastest/easiest way is with a regular expression.
     // Don't worry, the rules of using a <script> tag are really strict,
     // this will work.
-    let regexp = /<script[^>]*>([^]*?)<\/script\s*>/gim;
+    let regexp = /<script[^>]*?(?:>([^]*?)<\/script\s*>|\/>)/gim;
     let syntaxTrees = [];
     let scriptMatches = [];
     let scriptMatch;
@@ -54,7 +54,9 @@ Parser.prototype = {
     if (aSource.match(/^\s*</)) {
       // First non whitespace character is &lt, so most definitely HTML.
       while (scriptMatch = regexp.exec(aSource)) {
-        scriptMatches.push(scriptMatch[1]); // Contents are captured at index 1.
+        // Contents are captured at index 1 or nothing: Self-closing scripts
+        // won't capture code content
+        scriptMatches.push(scriptMatch[1] || "");
       }
     }
 
diff --git a/devtools/shared/webconsole/network-monitor.js b/devtools/shared/webconsole/network-monitor.js
index a3306957069..c49d67ce2db 100644
--- a/devtools/shared/webconsole/network-monitor.js
+++ b/devtools/shared/webconsole/network-monitor.js
@@ -524,11 +524,10 @@ NetworkMonitor.prototype = {
   owner: null,
 
   /**
-   * Whether to save the bodies of network requests and responses. Disabled by
-   * default to save memory.
+   * Whether to save the bodies of network requests and responses.
    * @type boolean
    */
-  saveRequestAndResponseBodies: false,
+  saveRequestAndResponseBodies: true,
 
   /**
    * Object that holds the HTTP activity objects for ongoing requests.
@@ -1243,7 +1242,7 @@ NetworkMonitorChild.prototype = {
   appId: null,
   owner: null,
   _netEvents: null,
-  _saveRequestAndResponseBodies: false,
+  _saveRequestAndResponseBodies: true,
 
   get saveRequestAndResponseBodies() {
     return this._saveRequestAndResponseBodies;
diff --git a/devtools/shared/webconsole/test/test_network_get.html b/devtools/shared/webconsole/test/test_network_get.html
index 5da7b446bd1..710c9b0d751 100644
--- a/devtools/shared/webconsole/test/test_network_get.html
+++ b/devtools/shared/webconsole/test/test_network_get.html
@@ -87,7 +87,7 @@ function onNetworkEventUpdate(aState, aType, aPacket)
           status: "200",
           statusText: "OK",
           headersSize: /^\d+$/,
-          discardResponseBody: true,
+          discardResponseBody: false,
         },
       };
       break;
@@ -104,8 +104,8 @@ function onNetworkEventUpdate(aState, aType, aPacket)
     case "responseContent":
       expectedPacket = {
         mimeType: "application/json",
-        contentSize: 0,
-        discardResponseBody: true,
+        contentSize: 1070,
+        discardResponseBody: false,
       };
       break;
     case "eventTimings":
@@ -180,7 +180,7 @@ function onRequestPostData(aState, aResponse)
   info("checking request POST data");
 
   ok(!aResponse.postData.text, "no request POST data");
-  ok(aResponse.postDataDiscarded, "request POST data was discarded");
+  ok(!aResponse.postDataDiscarded, "request POST data was not discarded");
 
   onResponseHeaders = onResponseHeaders.bind(null, aState);
   aState.client.getResponseHeaders(aState.netActor,
@@ -225,8 +225,8 @@ function onResponseContent(aState, aResponse)
 {
   info("checking response content");
 
-  ok(!aResponse.content.text, "no response content");
-  ok(aResponse.contentDiscarded, "response content was discarded");
+  ok(aResponse.content.text, "response content text");
+  ok(!aResponse.contentDiscarded, "response content was not discarded");
 
   onEventTimings = onEventTimings.bind(null, aState);
   aState.client.getEventTimings(aState.netActor,
diff --git a/devtools/shared/webconsole/test/test_network_longstring.html b/devtools/shared/webconsole/test/test_network_longstring.html
index 46b41e7ac6a..d5513689691 100644
--- a/devtools/shared/webconsole/test/test_network_longstring.html
+++ b/devtools/shared/webconsole/test/test_network_longstring.html
@@ -25,7 +25,7 @@ function startTest()
 
 function onAttach(aState, aResponse)
 {
-  info("enable network request and response body logging");
+  info("set long string length");
 
   window.ORIGINAL_LONG_STRING_LENGTH = DebuggerServer.LONG_STRING_LENGTH;
   window.ORIGINAL_LONG_STRING_INITIAL_LENGTH =
@@ -34,18 +34,6 @@ function onAttach(aState, aResponse)
   DebuggerServer.LONG_STRING_LENGTH = 400;
   DebuggerServer.LONG_STRING_INITIAL_LENGTH = 400;
 
-  onSetPreferences = onSetPreferences.bind(null, aState);
-  aState.client.setPreferences({
-    "NetworkMonitor.saveRequestAndResponseBodies": true,
-  }, onSetPreferences);
-}
-
-function onSetPreferences(aState, aResponse)
-{
-  is(aResponse.updated.length, 1, "updated prefs length");
-  is(aResponse.updated[0], "NetworkMonitor.saveRequestAndResponseBodies",
-     "updated prefs length");
-
   info("test network POST request");
 
   onNetworkEvent = onNetworkEvent.bind(null, aState);
diff --git a/devtools/shared/webconsole/test/test_network_post.html b/devtools/shared/webconsole/test/test_network_post.html
index 4679fad3bd5..d96b9b0b7c2 100644
--- a/devtools/shared/webconsole/test/test_network_post.html
+++ b/devtools/shared/webconsole/test/test_network_post.html
@@ -25,20 +25,6 @@ function startTest()
 
 function onAttach(aState, aResponse)
 {
-  info("enable network request and response body logging");
-
-  onSetPreferences = onSetPreferences.bind(null, aState);
-  aState.client.setPreferences({
-    "NetworkMonitor.saveRequestAndResponseBodies": true,
-  }, onSetPreferences);
-}
-
-function onSetPreferences(aState, aResponse)
-{
-  is(aResponse.updated.length, 1, "updated prefs length");
-  is(aResponse.updated[0], "NetworkMonitor.saveRequestAndResponseBodies",
-     "updated prefs length");
-
   info("test network POST request");
 
   onNetworkEvent = onNetworkEvent.bind(null, aState);
diff --git a/mobile/android/base/java/org/mozilla/gecko/BrowserApp.java b/mobile/android/base/java/org/mozilla/gecko/BrowserApp.java
index 84a3424b370..c387cd20b20 100644
--- a/mobile/android/base/java/org/mozilla/gecko/BrowserApp.java
+++ b/mobile/android/base/java/org/mozilla/gecko/BrowserApp.java
@@ -403,7 +403,7 @@ public class BrowserApp extends GeckoApp
         // This flow is from the option menu which has check to see if a bookmark was already added.
         // So, it is safe here to show the snackbar that bookmark_added without any checks.
 
-        final SnackbarCallback callback = new SnackbarCallback() {
+        final SnackbarHelper.SnackbarCallback callback = new SnackbarHelper.SnackbarCallback() {
             @Override
             public void onClick(View v) {
                 Telemetry.sendUIEvent(TelemetryContract.Event.SHOW, TelemetryContract.Method.TOAST, "bookmark_options");
@@ -411,18 +411,19 @@ public class BrowserApp extends GeckoApp
             }
         };
 
-        showSnackbar(getResources().getString(R.string.bookmark_added),
-                     Snackbar.LENGTH_LONG,
-                     getResources().getString(R.string.bookmark_options),
-                     callback);
+        SnackbarHelper.showSnackbarWithAction(this,
+                getResources().getString(R.string.bookmark_added),
+                Snackbar.LENGTH_LONG,
+                getResources().getString(R.string.bookmark_options),
+                callback);
     }
 
     private void showBookmarkRemovedSnackbar() {
-        showSnackbar(getResources().getString(R.string.bookmark_removed), Snackbar.LENGTH_SHORT, null, null);
+        SnackbarHelper.showSnackbar(this, getResources().getString(R.string.bookmark_removed), Snackbar.LENGTH_SHORT);
     }
 
     private void showSwitchToReadingListSnackbar(String message) {
-        final SnackbarCallback callback = new SnackbarCallback() {
+        final SnackbarHelper.SnackbarCallback callback = new SnackbarHelper.SnackbarCallback() {
             @Override
             public void onClick(View v) {
                 Telemetry.sendUIEvent(TelemetryContract.Event.SHOW, TelemetryContract.Method.TOAST, "reading_list");
@@ -432,7 +433,11 @@ public class BrowserApp extends GeckoApp
             }
         };
 
-        showSnackbar(message, Snackbar.LENGTH_LONG, getResources().getString(R.string.switch_button_message), callback);
+        SnackbarHelper.showSnackbarWithAction(this,
+                message,
+                Snackbar.LENGTH_LONG,
+                getResources().getString(R.string.switch_button_message),
+                callback);
     }
 
     public void onAddedToReadingList(String url) {
@@ -444,7 +449,9 @@ public class BrowserApp extends GeckoApp
     }
 
     public void onRemovedFromReadingList(String url) {
-        showSnackbar(getResources().getString(R.string.reading_list_removed), Snackbar.LENGTH_SHORT, null, null);
+        SnackbarHelper.showSnackbar(this,
+                getResources().getString(R.string.reading_list_removed),
+                Snackbar.LENGTH_SHORT);
     }
 
     @Override
@@ -2726,10 +2733,8 @@ public class BrowserApp extends GeckoApp
 
         @Override
         public boolean onInterceptTouchEvent(View view, MotionEvent event) {
-            if (event.getActionMasked() == MotionEvent.ACTION_DOWN
-                    && mSnackbar != null
-                    && mSnackbar.isShown()) {
-                mSnackbar.dismiss();
+            if (event.getActionMasked() == MotionEvent.ACTION_DOWN) {
+                SnackbarHelper.dismissCurrentSnackbar();
             }
 
             // Only try to hide the button toast if it's already inflated and if we are starting a tap action.
@@ -3731,7 +3736,7 @@ public class BrowserApp extends GeckoApp
         // hold a reference to the Tab itself in the anonymous listener class.
         final int newTabId = newTab.getId();
 
-        final SnackbarCallback callback = new SnackbarCallback() {
+        final SnackbarHelper.SnackbarCallback callback = new SnackbarHelper.SnackbarCallback() {
             @Override
             public void onClick(View v) {
                 Telemetry.sendUIEvent(TelemetryContract.Event.SHOW, TelemetryContract.Method.TOAST, "switchtab");
@@ -3745,7 +3750,7 @@ public class BrowserApp extends GeckoApp
                 getResources().getString(R.string.new_tab_opened);
         final String buttonMessage = getResources().getString(R.string.switch_button_message);
 
-        showSnackbar(message, Snackbar.LENGTH_LONG, buttonMessage, callback);
+        SnackbarHelper.showSnackbarWithAction(this, message, Snackbar.LENGTH_LONG, buttonMessage, callback);
     }
 
     // BrowserSearch.OnSearchListener
diff --git a/mobile/android/base/java/org/mozilla/gecko/EditBookmarkDialog.java b/mobile/android/base/java/org/mozilla/gecko/EditBookmarkDialog.java
index cacd442daed..ddd7482b489 100644
--- a/mobile/android/base/java/org/mozilla/gecko/EditBookmarkDialog.java
+++ b/mobile/android/base/java/org/mozilla/gecko/EditBookmarkDialog.java
@@ -217,8 +217,9 @@ public class EditBookmarkDialog {
 
                     @Override
                     public void onPostExecute(Void result) {
-                        View view = ((Activity)context).findViewById(android.R.id.content);
-                        Snackbar.make(view, R.string.bookmark_updated, Snackbar.LENGTH_SHORT).show();
+                        SnackbarHelper.showSnackbar((Activity) context,
+                                context.getString(R.string.bookmark_updated),
+                                Snackbar.LENGTH_SHORT);
                     }
                 }).execute();
             }
diff --git a/mobile/android/base/java/org/mozilla/gecko/GeckoApp.java b/mobile/android/base/java/org/mozilla/gecko/GeckoApp.java
index 1df88ead980..d613f1355e8 100644
--- a/mobile/android/base/java/org/mozilla/gecko/GeckoApp.java
+++ b/mobile/android/base/java/org/mozilla/gecko/GeckoApp.java
@@ -5,7 +5,6 @@
 
 package org.mozilla.gecko;
 
-import org.mozilla.gecko.AppConstants;
 import android.widget.AdapterView;
 import android.widget.Button;
 import org.mozilla.gecko.AppConstants.Versions;
@@ -50,7 +49,6 @@ import org.mozilla.gecko.widget.ButtonToast;
 import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.app.AlertDialog;
-import android.app.Dialog;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.Intent;
@@ -76,9 +74,7 @@ import android.os.Process;
 import android.os.StrictMode;
 import android.provider.ContactsContract;
 import android.provider.MediaStore.Images.Media;
-import android.support.annotation.Nullable;
 import android.support.design.widget.Snackbar;
-import android.support.v4.content.ContextCompat;
 import android.text.TextUtils;
 import android.util.AttributeSet;
 import android.util.Base64;
@@ -196,7 +192,6 @@ public abstract class GeckoApp
     protected DoorHangerPopup mDoorHangerPopup;
     protected FormAssistPopup mFormAssistPopup;
     protected ButtonToast mToast;
-    protected Snackbar mSnackbar;
 
     protected LayerView mLayerView;
     private AbsoluteLayout mPluginContainer;
@@ -579,7 +574,7 @@ public abstract class GeckoApp
                     ThreadUtils.postToUiThread(new Runnable() {
                         @Override
                         public void run() {
-                            showSnackbar(getString(resId), Snackbar.LENGTH_SHORT, null, null);
+                            SnackbarHelper.showSnackbar(GeckoApp.this, getString(resId), Snackbar.LENGTH_SHORT);
                         }
                     });
                 }
@@ -651,17 +646,7 @@ public abstract class GeckoApp
             Telemetry.sendUIEvent(TelemetryContract.Event.SHARE, TelemetryContract.Method.LIST, "text");
 
         } else if ("Snackbar:Show".equals(event)) {
-            final String msg = message.getString("message");
-            final int duration = message.getInt("duration");
-
-            NativeJSObject action = message.optObject("action", null);
-
-            final SnackbarEventCallback snackbarCallback = new SnackbarEventCallback(callback);
-
-            showSnackbar(msg,
-                    duration,
-                    action != null ? action.optString("label", null) : null,
-                    snackbarCallback);
+            SnackbarHelper.showSnackbar(this, message, callback);
         } else if ("SystemUI:Visibility".equals(event)) {
             setSystemUiVisible(message.getBoolean("visible"));
 
@@ -844,58 +829,6 @@ public abstract class GeckoApp
         return mToast;
     }
 
-    void showSnackbar(final String message, final int duration, @Nullable final String action,
-                      final @Nullable SnackbarCallback callback) {
-        final Snackbar snackbar = Snackbar.make(mRootLayout, message, duration);
-
-        if (callback != null && !TextUtils.isEmpty(action)) {
-            snackbar.setAction(action, callback);
-            snackbar.setActionTextColor(ContextCompat.getColor(this, R.color.fennec_ui_orange));
-            snackbar.setCallback(callback);
-        }
-
-        snackbar.show();
-
-        this.mSnackbar = snackbar;
-    }
-
-    /**
-     * Combined interface for handling all callbacks from a snackbar because anonymous classes can only extend one
-     * interface or class.
-     */
-    public static abstract class SnackbarCallback extends Snackbar.Callback implements View.OnClickListener {};
-
-    /**
-     * SnackbarCallback implementation for delegating snackbar events to an EventCallback.
-     */
-    private static class SnackbarEventCallback extends SnackbarCallback {
-        private EventCallback callback;
-
-        public SnackbarEventCallback(EventCallback callback) {
-            this.callback = callback;
-        }
-
-        @Override
-        public synchronized void onClick(View view) {
-            if (callback == null) {
-                return;
-            }
-
-            callback.sendSuccess(null);
-            callback = null;
-        }
-
-        @Override
-        public synchronized void onDismissed(Snackbar snackbar, int event) {
-            if (callback == null || event == Snackbar.Callback.DISMISS_EVENT_ACTION) {
-                return;
-            }
-
-            callback.sendError(null);
-            callback = null;
-        }
-    }
-
     void showButtonToast(final String message, final String duration,
                          final String buttonText, final String buttonIcon,
                          final String buttonId) {
@@ -1061,12 +994,12 @@ public abstract class GeckoApp
                 File dcimDir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
 
                 if (!dcimDir.mkdirs() && !dcimDir.isDirectory()) {
-                    showSnackbar(getString(R.string.set_image_path_fail), Snackbar.LENGTH_SHORT, null, null);
+                    SnackbarHelper.showSnackbar(this, getString(R.string.set_image_path_fail), Snackbar.LENGTH_SHORT);
                     return;
                 }
                 String path = Media.insertImage(getContentResolver(),image, null, null);
                 if (path == null) {
-                    showSnackbar(getString(R.string.set_image_path_fail), Snackbar.LENGTH_SHORT, null, null);
+                    SnackbarHelper.showSnackbar(this, getString(R.string.set_image_path_fail), Snackbar.LENGTH_SHORT);
                     return;
                 }
                 final Intent intent = new Intent(Intent.ACTION_ATTACH_DATA);
@@ -1083,7 +1016,7 @@ public abstract class GeckoApp
                 };
                 ActivityHandlerHelper.startIntentForActivity(this, chooser, handler);
             } else {
-                showSnackbar(getString(R.string.set_image_fail), Snackbar.LENGTH_SHORT, null, null);
+                SnackbarHelper.showSnackbar(this, getString(R.string.set_image_fail), Snackbar.LENGTH_SHORT);
             }
         } catch(OutOfMemoryError ome) {
             Log.e(LOGTAG, "Out of Memory when converting to byte array", ome);
diff --git a/mobile/android/base/java/org/mozilla/gecko/GeckoAppShell.java b/mobile/android/base/java/org/mozilla/gecko/GeckoAppShell.java
index 7fd5669e1a6..2fee0c6cc15 100644
--- a/mobile/android/base/java/org/mozilla/gecko/GeckoAppShell.java
+++ b/mobile/android/base/java/org/mozilla/gecko/GeckoAppShell.java
@@ -2673,8 +2673,10 @@ public class GeckoAppShell
 
     // Don't fail silently, tell the user that we weren't able to share the image
     private static final void showImageShareFailureSnackbar() {
-        View rootView = ((Activity)getContext()).findViewById(android.R.id.content);
-        Snackbar.make(rootView, R.string.share_image_failed, Snackbar.LENGTH_SHORT).show();
+        SnackbarHelper.showSnackbar((Activity) getContext(),
+                getApplicationContext().getString(R.string.share_image_failed),
+                Snackbar.LENGTH_SHORT
+        );
     }
 
     @WrapForJNI(allowMultithread = true)
diff --git a/mobile/android/base/java/org/mozilla/gecko/SnackbarHelper.java b/mobile/android/base/java/org/mozilla/gecko/SnackbarHelper.java
new file mode 100644
index 00000000000..806fad3ed88
--- /dev/null
+++ b/mobile/android/base/java/org/mozilla/gecko/SnackbarHelper.java
@@ -0,0 +1,143 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import org.mozilla.gecko.util.EventCallback;
+import org.mozilla.gecko.util.NativeJSObject;
+
+import android.app.Activity;
+import android.support.design.widget.Snackbar;
+import android.support.v4.content.ContextCompat;
+import android.text.TextUtils;
+import android.view.View;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * Helper class for creating and dismissing snackbars. Use this class to guarantee a consistent style and behavior
+ * across the app.
+ */
+public class SnackbarHelper {
+    /**
+     * Combined interface for handling all callbacks from a snackbar because anonymous classes can only extend one
+     * interface or class.
+     */
+    public static abstract class SnackbarCallback extends Snackbar.Callback implements View.OnClickListener {}
+
+    /**
+     * SnackbarCallback implementation for delegating snackbar events to an EventCallback.
+     */
+    private static class SnackbarEventCallback extends SnackbarCallback {
+        private EventCallback callback;
+
+        public SnackbarEventCallback(EventCallback callback) {
+            this.callback = callback;
+        }
+
+        @Override
+        public synchronized void onClick(View view) {
+            if (callback == null) {
+                return;
+            }
+
+            callback.sendSuccess(null);
+            callback = null; // Releasing reference. We only want to execute the callback once.
+        }
+
+        @Override
+        public synchronized void onDismissed(Snackbar snackbar, int event) {
+            if (callback == null || event == Snackbar.Callback.DISMISS_EVENT_ACTION) {
+                return;
+            }
+
+            callback.sendError(null);
+            callback = null; // Releasing reference. We only want to execute the callback once.
+        }
+    }
+
+    private static final Object currentSnackbarLock = new Object();
+    private static WeakReference<Snackbar> currentSnackbar = new WeakReference<>(null); // Guarded by 'currentSnackbarLock'
+
+    /**
+     * Show a snackbar to display a message.
+     *
+     * @param activity Activity to show the snackbar in.
+     * @param message The text to show. Can be formatted text.
+     * @param duration How long to display the message.
+     */
+    public static void showSnackbar(Activity activity, String message, int duration) {
+        showSnackbarWithAction(activity, message, duration, null, null);
+    }
+
+    /**
+     * Build and show a snackbar from a Gecko Snackbar:Show event.
+     */
+    public static void showSnackbar(Activity activity, final NativeJSObject object, final EventCallback callback) {
+        final String message = object.getString("message");
+        final int duration = object.getInt("duration");
+
+        NativeJSObject action = object.optObject("action", null);
+
+        showSnackbarWithAction(activity,
+                message,
+                duration,
+                action != null ? action.optString("label", null) : null,
+                new SnackbarHelper.SnackbarEventCallback(callback));
+    }
+
+    /**
+     * Show a snackbar to display a message and an action.
+     *
+     * @param activity Activity to show the snackbar in.
+     * @param message The text to show. Can be formatted text.
+     * @param duration How long to display the message.
+     * @param action Action text to display.
+     * @param callback Callback to be invoked when the action is clicked or the snackbar is dismissed.
+     */
+    public static void showSnackbarWithAction(Activity activity, String message, int duration, String action, SnackbarCallback callback) {
+        final View parentView = findBestParentView(activity);
+        final Snackbar snackbar = Snackbar.make(parentView, message, duration);
+
+        if (callback != null && !TextUtils.isEmpty(action)) {
+            snackbar.setAction(action, callback);
+            snackbar.setActionTextColor(ContextCompat.getColor(activity, R.color.fennec_ui_orange));
+            snackbar.setCallback(callback);
+        }
+
+        snackbar.show();
+
+        synchronized (currentSnackbarLock) {
+            currentSnackbar = new WeakReference<>(snackbar);
+        }
+    }
+
+    /**
+     * Dismiss the currently visible snackbar.
+     */
+    public static void dismissCurrentSnackbar() {
+        synchronized (currentSnackbarLock) {
+            final Snackbar snackbar = currentSnackbar.get();
+            if (snackbar != null && snackbar.isShown()) {
+                snackbar.dismiss();
+            }
+        }
+    }
+
+    /**
+     * Find the best parent view to hold the Snackbar's view. The Snackbar implementation of the support
+     * library will use this view to walk up the view tree to find an actual suitable parent (if needed).
+     */
+    private static View findBestParentView(Activity activity) {
+        if (activity instanceof GeckoApp) {
+            final View view = activity.findViewById(R.id.root_layout);
+            if (view != null) {
+                return view;
+            }
+        }
+
+        return activity.findViewById(android.R.id.content);
+    }
+}
diff --git a/mobile/android/base/java/org/mozilla/gecko/dlc/catalog/DownloadContentBootstrap.java b/mobile/android/base/java/org/mozilla/gecko/dlc/catalog/DownloadContentBootstrap.java
index eae051df93b..254a57385e0 100644
--- a/mobile/android/base/java/org/mozilla/gecko/dlc/catalog/DownloadContentBootstrap.java
+++ b/mobile/android/base/java/org/mozilla/gecko/dlc/catalog/DownloadContentBootstrap.java
@@ -21,8 +21,8 @@ import java.util.List;
 
         return Arrays.asList(
                 new DownloadContent.Builder()
-                        .setId("bff50e08-7bbc-4d77-a907-bb0a54434bee")
-                        .setLocation("fonts/CharisSILCompact-B.ttf.gz")
+                        .setId("c40929cf-7f4c-fa72-3dc9-12cadf56905d")
+                        .setLocation("fonts/ff7ecae7669a51d5fa6a5f8e703278ebda3a68f51bc49c4321bde4438020d639.gz")
                         .setFilename("CharisSILCompact-B.ttf")
                         .setChecksum("699d958b492eda0cc2823535f8567d0393090e3842f6df3c36dbe7239cb80b6d")
                         .setDownloadChecksum("ff7ecae7669a51d5fa6a5f8e703278ebda3a68f51bc49c4321bde4438020d639")
@@ -32,8 +32,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("68c6472d-94a6-4fb2-8525-78e427b022fe")
-                        .setLocation("fonts/CharisSILCompact-BI.ttf.gz")
+                        .setId("6d265876-85ed-0917-fdc8-baf583ca2cba")
+                        .setLocation("fonts/dfb6d583edd27d5e6d91d479e6c8a5706275662c940c65b70911493bb279904a.gz")
                         .setFilename("CharisSILCompact-BI.ttf")
                         .setChecksum("82465e747b4f41471dbfd942842b2ee810749217d44b55dbc43623b89f9c7d9b")
                         .setDownloadChecksum("dfb6d583edd27d5e6d91d479e6c8a5706275662c940c65b70911493bb279904a")
@@ -43,8 +43,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("33d0ce0d-9c48-4a37-8b74-81cce872061b")
-                        .setLocation("fonts/CharisSILCompact-I.ttf.gz")
+                        .setId("8460dc6d-d129-fd1a-24b6-343dbf6531dd")
+                        .setLocation("fonts/5a257ec3c5226e7be0be65e463f5b22eff108da853b9ff7bc47f1733b1ddacf2.gz")
                         .setFilename("CharisSILCompact-I.ttf")
                         .setChecksum("ab3ed6f2a4d4c2095b78227bd33155d7ccd05a879c107a291912640d4d64f767")
                         .setDownloadChecksum("5a257ec3c5226e7be0be65e463f5b22eff108da853b9ff7bc47f1733b1ddacf2")
@@ -54,8 +54,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("7e274cdc-4216-4dc0-b7a5-8ec333f0c287")
-                        .setLocation("fonts/CharisSILCompact-R.ttf.gz")
+                        .setId("c906275c-3747-fe27-426f-6187526a6f06")
+                        .setLocation("fonts/cab284228b8dfe8ef46c3f1af70b5b6f9e92878f05e741ecc611e5e750a4a3b3.gz")
                         .setFilename("CharisSILCompact-R.ttf")
                         .setChecksum("4ed509317f1bb441b185ea13bf1c9d19d1a0b396962efa3b5dc3190ad88f2067")
                         .setDownloadChecksum("cab284228b8dfe8ef46c3f1af70b5b6f9e92878f05e741ecc611e5e750a4a3b3")
@@ -65,8 +65,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("b144002f-d5de-448c-8952-da1e405e022f")
-                        .setLocation("fonts/ClearSans-Bold.ttf.gz")
+                        .setId("ff5deecc-6ecc-d816-bb51-65face460119")
+                        .setLocation("fonts/d95168996dc932e6504cb5448fcb759e0ee6e66c5c8603293b046d28ab589cce.gz")
                         .setFilename("ClearSans-Bold.ttf")
                         .setChecksum("385d0a293c1714770e198f7c762ab32f7905a0ed9d2993f69d640bd7232b4b70")
                         .setDownloadChecksum("d95168996dc932e6504cb5448fcb759e0ee6e66c5c8603293b046d28ab589cce")
@@ -76,8 +76,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("f07502f5-e4c5-41a8-8788-89717397a98d")
-                        .setLocation("fonts/ClearSans-BoldItalic.ttf.gz")
+                        .setId("a173d1db-373b-ce42-1335-6b3285cfdebd")
+                        .setLocation("fonts/f5e18f4acc4ceaeca9e081b1be79cd6034e0dc7ad683fa240195fd6c838452e0.gz")
                         .setFilename("ClearSans-BoldItalic.ttf")
                         .setChecksum("7bce66864e38eecd7c94b6657b9b38c35ebfacf8046bfb1247e08f07fe933198")
                         .setDownloadChecksum("f5e18f4acc4ceaeca9e081b1be79cd6034e0dc7ad683fa240195fd6c838452e0")
@@ -87,8 +87,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("afafc7ef-f516-42da-88d4-d8435f65541b")
-                        .setLocation("fonts/ClearSans-Italic.ttf.gz")
+                        .setId("e65c66df-0088-940d-ca5c-207c22118c0e")
+                        .setLocation("fonts/56d12114ac15d913d7d9876c698889cd25f26e14966a8bd7424aeb0f61ffaf87.gz")
                         .setFilename("ClearSans-Italic.ttf")
                         .setChecksum("87c13c5fbae832e4f85c3bd46fcbc175978234f39be5fe51c4937be4cbff3b68")
                         .setDownloadChecksum("56d12114ac15d913d7d9876c698889cd25f26e14966a8bd7424aeb0f61ffaf87")
@@ -98,8 +98,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("28521d9b-ac2e-45d0-89b6-a4c9076dbf6d")
-                        .setLocation("fonts/ClearSans-Light.ttf.gz")
+                        .setId("25610abb-5dc8-fd75-40e7-990507f010c4")
+                        .setLocation("fonts/1fc716662866b9c01e32dda3fc9c54ca3e57de8c6ac523f46305d8ae6c0a9cf4.gz")
                         .setFilename("ClearSans-Light.ttf")
                         .setChecksum("e4885f6188e7a8587f5621c077c6c1f5e8d3739dffc8f4d055c2ba87568c750a")
                         .setDownloadChecksum("1fc716662866b9c01e32dda3fc9c54ca3e57de8c6ac523f46305d8ae6c0a9cf4")
@@ -109,8 +109,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("13f01bf4-da71-4673-9c60-ec0e9a45c38c")
-                        .setLocation("fonts/ClearSans-Medium.ttf.gz")
+                        .setId("ffe40339-a096-2262-c3f8-54af75c81fe6")
+                        .setLocation("fonts/a29184ec6621dbd3bc6ae1e30bba70c479d1001bca647ea4a205ecb64d5a00a0.gz")
                         .setFilename("ClearSans-Medium.ttf")
                         .setChecksum("5d0e0115f3a3ed4be3eda6d7eabb899bb9a361292802e763d53c72e00f629da1")
                         .setDownloadChecksum("a29184ec6621dbd3bc6ae1e30bba70c479d1001bca647ea4a205ecb64d5a00a0")
@@ -120,8 +120,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("73104370-c7ee-4b5b-bb37-392a4e66f65a")
-                        .setLocation("fonts/ClearSans-MediumItalic.ttf.gz")
+                        .setId("139a94be-ac69-0264-c9cc-8f2d071fd29d")
+                        .setLocation("fonts/a381a3d4060e993af440a7b72fed29fa3a488536cc451d7c435d5fae1256318b.gz")
                         .setFilename("ClearSans-MediumItalic.ttf")
                         .setChecksum("937dda88b26469306258527d38e42c95e27e7ebb9f05bd1d7c5d706a3c9541d7")
                         .setDownloadChecksum("a381a3d4060e993af440a7b72fed29fa3a488536cc451d7c435d5fae1256318b")
@@ -131,8 +131,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("274f3718-f6e0-40b4-b52a-44812ec3ea9e")
-                        .setLocation("fonts/ClearSans-Regular.ttf.gz")
+                        .setId("b887012a-01e1-7c94-fdcb-ca44d5b974a2")
+                        .setLocation("fonts/87dec7f0331e19b293fc510f2764b9bd1b94595ac279cf9414f8d03c5bf34dca.gz")
                         .setFilename("ClearSans-Regular.ttf")
                         .setChecksum("9b91bbdb95ffa6663da24fdaa8ee06060cd0a4d2dceaf1ffbdda00e04915ee5b")
                         .setDownloadChecksum("87dec7f0331e19b293fc510f2764b9bd1b94595ac279cf9414f8d03c5bf34dca")
@@ -142,8 +142,8 @@ import java.util.List;
                         .build(),
 
                 new DownloadContent.Builder()
-                        .setId("77803858-3cfb-4a0d-a1d3-fa1bf8a6c604")
-                        .setLocation("fonts/ClearSans-Thin.ttf.gz")
+                        .setId("c8703652-d317-0356-0bf8-95441a5b2c9b")
+                        .setLocation("fonts/64300b48b2867e5642212690f0ff9ea3988f47790311c444a81d25213b4102aa.gz")
                         .setFilename("ClearSans-Thin.ttf")
                         .setChecksum("07b0db85a3ad99afeb803f0f35631436a7b4c67ac66d0c7f77d26a47357c592a")
                         .setDownloadChecksum("64300b48b2867e5642212690f0ff9ea3988f47790311c444a81d25213b4102aa")
diff --git a/mobile/android/base/java/org/mozilla/gecko/home/HomeFragment.java b/mobile/android/base/java/org/mozilla/gecko/home/HomeFragment.java
index 5a9f690c2df..d8c617a9cb2 100644
--- a/mobile/android/base/java/org/mozilla/gecko/home/HomeFragment.java
+++ b/mobile/android/base/java/org/mozilla/gecko/home/HomeFragment.java
@@ -15,6 +15,7 @@ import org.mozilla.gecko.GeckoProfile;
 import org.mozilla.gecko.R;
 import org.mozilla.gecko.ReaderModeUtils;
 import org.mozilla.gecko.Restrictions;
+import org.mozilla.gecko.SnackbarHelper;
 import org.mozilla.gecko.Telemetry;
 import org.mozilla.gecko.TelemetryContract;
 import org.mozilla.gecko.db.BrowserDB;
@@ -413,8 +414,9 @@ public abstract class HomeFragment extends Fragment {
 
         @Override
         public void onPostExecute(Void result) {
-            View rootView = ((Activity)mContext).findViewById(android.R.id.content);
-            Snackbar.make(rootView, R.string.page_removed, Snackbar.LENGTH_SHORT).show();
+            SnackbarHelper.showSnackbar((Activity) mContext,
+                    mContext.getString(R.string.page_removed),
+                    Snackbar.LENGTH_SHORT);
         }
     }
 }
diff --git a/mobile/android/base/java/org/mozilla/gecko/preferences/GeckoPreferences.java b/mobile/android/base/java/org/mozilla/gecko/preferences/GeckoPreferences.java
index a4db2c67560..f2250d7899e 100644
--- a/mobile/android/base/java/org/mozilla/gecko/preferences/GeckoPreferences.java
+++ b/mobile/android/base/java/org/mozilla/gecko/preferences/GeckoPreferences.java
@@ -25,6 +25,7 @@ import org.mozilla.gecko.Locales;
 import org.mozilla.gecko.PrefsHelper;
 import org.mozilla.gecko.R;
 import org.mozilla.gecko.Restrictions;
+import org.mozilla.gecko.SnackbarHelper;
 import org.mozilla.gecko.Telemetry;
 import org.mozilla.gecko.TelemetryContract;
 import org.mozilla.gecko.TelemetryContract.Method;
@@ -34,9 +35,12 @@ import org.mozilla.gecko.restrictions.Restrictable;
 import org.mozilla.gecko.tabqueue.TabQueueHelper;
 import org.mozilla.gecko.updater.UpdateService;
 import org.mozilla.gecko.updater.UpdateServiceHelper;
+import org.mozilla.gecko.util.EventCallback;
 import org.mozilla.gecko.util.GeckoEventListener;
 import org.mozilla.gecko.util.HardwareUtils;
 import org.mozilla.gecko.util.InputOptionsUtils;
+import org.mozilla.gecko.util.NativeEventListener;
+import org.mozilla.gecko.util.NativeJSObject;
 import org.mozilla.gecko.util.ThreadUtils;
 import org.mozilla.gecko.widget.FloatingHintEditText;
 
@@ -92,6 +96,7 @@ extends PreferenceActivity
 implements
 GeckoActivityStatus,
 GeckoEventListener,
+NativeEventListener,
 OnPreferenceChangeListener,
 OnSharedPreferenceChangeListener
 {
@@ -361,9 +366,12 @@ OnSharedPreferenceChangeListener
             addPreferencesFromResource(res);
         }
 
-        EventDispatcher.getInstance().registerGeckoThreadListener(this,
+        EventDispatcher.getInstance().registerGeckoThreadListener((GeckoEventListener) this,
             "Sanitize:Finished");
 
+        EventDispatcher.getInstance().registerGeckoThreadListener((NativeEventListener) this,
+            "Snackbar:Show");
+
         // Add handling for long-press click.
         // This is only for Android 3.0 and below (which use the long-press-context-menu paradigm).
         final ListView mListView = getListView();
@@ -512,8 +520,12 @@ OnSharedPreferenceChangeListener
     @Override
     protected void onDestroy() {
         super.onDestroy();
-        EventDispatcher.getInstance().unregisterGeckoThreadListener(this,
+        EventDispatcher.getInstance().unregisterGeckoThreadListener((GeckoEventListener) this,
             "Sanitize:Finished");
+
+        EventDispatcher.getInstance().unregisterGeckoThreadListener((NativeEventListener) this,
+            "Snackbar:Show");
+
         if (mPrefsRequestId > 0) {
             PrefsHelper.removeObserver(mPrefsRequestId);
         }
@@ -617,19 +629,23 @@ OnSharedPreferenceChangeListener
             if (event.equals("Sanitize:Finished")) {
                 boolean success = message.getBoolean("success");
                 final int stringRes = success ? R.string.private_data_success : R.string.private_data_fail;
-                final Context context = this;
-                ThreadUtils.postToUiThread(new Runnable () {
-                    @Override
-                    public void run() {
-                        Snackbar.make(findViewById(android.R.id.content), stringRes, Snackbar.LENGTH_SHORT).show();
-                    }
-                });
+
+                SnackbarHelper.showSnackbar(GeckoPreferences.this,
+                        getString(stringRes),
+                        Snackbar.LENGTH_SHORT);
             }
         } catch (Exception e) {
             Log.e(LOGTAG, "Exception handling message \"" + event + "\":", e);
         }
     }
 
+    @Override
+    public void handleMessage(final String event, final NativeJSObject message, final EventCallback callback) {
+        if ("Snackbar:Show".equals(event)) {
+            SnackbarHelper.showSnackbar(this, message, callback);
+        }
+    }
+
     /**
       * Initialize all of the preferences (native of Gecko ones) for this screen.
       *
diff --git a/mobile/android/base/java/org/mozilla/gecko/preferences/SearchEnginePreference.java b/mobile/android/base/java/org/mozilla/gecko/preferences/SearchEnginePreference.java
index 773c535c96d..ff641895745 100644
--- a/mobile/android/base/java/org/mozilla/gecko/preferences/SearchEnginePreference.java
+++ b/mobile/android/base/java/org/mozilla/gecko/preferences/SearchEnginePreference.java
@@ -7,6 +7,7 @@ package org.mozilla.gecko.preferences;
 import org.json.JSONException;
 import org.json.JSONObject;
 import org.mozilla.gecko.R;
+import org.mozilla.gecko.SnackbarHelper;
 import org.mozilla.gecko.favicons.Favicons;
 import org.mozilla.gecko.favicons.OnFaviconLoadedListener;
 import org.mozilla.gecko.favicons.decoders.FaviconDecoder;
@@ -89,13 +90,12 @@ public class SearchEnginePreference extends CustomListPreference {
         // If this is the last engine, then we are the default, and none of the options
         // on this menu can do anything.
         if (mParentCategory.getPreferenceCount() == 1) {
-            ThreadUtils.postToUiThread(new Runnable() {
-                @Override
-                public void run() {
-                    Activity activity = (Activity)getContext();
-                    Snackbar.make(activity.findViewById(android.R.id.content), R.string.pref_search_last_toast, Snackbar.LENGTH_SHORT).show();
-                }
-            });
+            Activity activity = (Activity) getContext();
+
+            SnackbarHelper.showSnackbar(activity,
+                    activity.getString(R.string.pref_search_last_toast),
+                    Snackbar.LENGTH_SHORT);
+
             return;
         }
 
diff --git a/mobile/android/base/moz.build b/mobile/android/base/moz.build
index 697a80c3f32..bcb00392662 100644
--- a/mobile/android/base/moz.build
+++ b/mobile/android/base/moz.build
@@ -509,6 +509,7 @@ gbjar.sources += ['java/org/mozilla/gecko/' + x for x in [
     'SharedPreferencesHelper.java',
     'SiteIdentity.java',
     'SmsManager.java',
+    'SnackbarHelper.java',
     'sqlite/ByteBufferInputStream.java',
     'sqlite/MatrixBlobCursor.java',
     'sqlite/SQLiteBridge.java',
diff --git a/mobile/android/locales/Makefile.in b/mobile/android/locales/Makefile.in
index ebd054dbdd5..b8e541ba8d9 100644
--- a/mobile/android/locales/Makefile.in
+++ b/mobile/android/locales/Makefile.in
@@ -82,6 +82,6 @@ ident:
 merge-%:
 ifdef LOCALE_MERGEDIR
 	$(RM) -rf $(LOCALE_MERGEDIR)
-	MACOSX_DEPLOYMENT_TARGET= compare-locales -m $(LOCALE_MERGEDIR) $(srcdir)/l10n.ini $(L10NBASEDIR) $*
+	$(topsrcdir)/mach compare-locales --merge-dir $(LOCALE_MERGEDIR) $*
 endif
 	@echo
diff --git a/mobile/android/themes/core/content.css b/mobile/android/themes/core/content.css
index 0696ecd8ff7..c4ef17baa33 100644
--- a/mobile/android/themes/core/content.css
+++ b/mobile/android/themes/core/content.css
@@ -71,7 +71,7 @@ xul|scrollbarbutton[sbattr="scrollbar-bottom-top"] {
   display: none;
 }
 
-xul|thumb {
+xul|scrollbar xul|thumb {
   background-color: rgba(0, 0, 0, 0.4) !important;
   -moz-border-top-colors: none !important;
   -moz-border-bottom-colors: none !important;
diff --git a/python/compare-locales/mach_commands.py b/python/compare-locales/mach_commands.py
index d0dc22e4f75..a42c6e7311a 100644
--- a/python/compare-locales/mach_commands.py
+++ b/python/compare-locales/mach_commands.py
@@ -70,7 +70,7 @@ class CompareLocales(MachCommandBase):
                 merge_dir = mozpath.join(
                     self.topobjdir,
                     self.substs['MOZ_BUILD_APP'],
-                    'locales', 'merge-{ab_CD}'
+                    'locales', 'merge-dir-{ab_CD}'
                 )
             except Exception:
                 pass
diff --git a/testing/mozharness/mozharness/mozilla/l10n/locales.py b/testing/mozharness/mozharness/mozilla/l10n/locales.py
index 395f78243ae..1389092258b 100755
--- a/testing/mozharness/mozharness/mozilla/l10n/locales.py
+++ b/testing/mozharness/mozharness/mozilla/l10n/locales.py
@@ -31,6 +31,21 @@ class LocalesMixin(ChunkingMixin):
         self.gecko_locale_revisions = None
         self.l10n_revisions = {}
 
+    def _get_mach_executable(self):
+        python = self.query_exe('python2.7')
+        return [python, 'mach']
+
+    def _mach(self, target, env, error_list=None, halt_on_failure=True,
+              output_parser=None):
+        dirs = self.query_abs_dirs()
+        mach = self._get_mach_executable()
+        return self.run_command(mach + target,
+                                error_list=error_list,
+                                halt_on_failure=True,
+                                env=env,
+                                cwd=dirs['abs_mozilla_dir'],
+                                output_parser=None)
+
     def query_locales(self):
         if self.locales is not None:
             return self.locales
@@ -141,20 +156,13 @@ class LocalesMixin(ChunkingMixin):
 
     def run_compare_locales(self, locale, halt_on_failure=False):
         dirs = self.query_abs_dirs()
-        compare_locales_script = os.path.join(dirs['abs_compare_locales_dir'],
-                                              'scripts', 'compare-locales')
-        env = self.query_env(partial_env={'PYTHONPATH':
-                             os.path.join(dirs['abs_compare_locales_dir'],
-                                          'lib')})
+        env = self.query_bootstrap_env()
         compare_locales_error_list = list(PythonErrorList)
-        self.rmtree(dirs['abs_merge_dir'])
-        self.mkdir_p(dirs['abs_merge_dir'])
-        command = "python %s -m %s l10n.ini %s %s" % (compare_locales_script,
-                  dirs['abs_merge_dir'], dirs['abs_l10n_dir'], locale)
+        command = ['compare-locales',
+                  '--merge-dir', dirs['abs_merge_dir'], locale]
         self.info("*** BEGIN compare-locales %s" % locale)
-        status = self.run_command(command, error_list=compare_locales_error_list,
-                                  cwd=dirs['abs_locales_src_dir'], env=env,
-                                  halt_on_failure=halt_on_failure)
+        status = self._mach(command, env, error_list=compare_locales_error_list,
+                            halt_on_failure=halt_on_failure)
         self.info("*** END compare-locales %s" % locale)
         return status
 
@@ -187,8 +195,6 @@ class LocalesMixin(ChunkingMixin):
                                                  'merged')
             dirs['abs_locales_dir'] = os.path.join(dirs['abs_objdir'],
                                                    c['locales_dir'])
-        dirs['abs_compare_locales_dir'] = os.path.join(dirs['abs_work_dir'],
-                                                       'compare-locales')
         for key in dirs.keys():
             if key not in abs_dirs:
                 abs_dirs[key] = dirs[key]
diff --git a/testing/mozharness/scripts/desktop_l10n.py b/testing/mozharness/scripts/desktop_l10n.py
index f0a571deb18..0abf78f218a 100755
--- a/testing/mozharness/scripts/desktop_l10n.py
+++ b/testing/mozharness/scripts/desktop_l10n.py
@@ -606,25 +606,12 @@ class DesktopSingleLocale(LocalesMixin, ReleaseMixin, MockMixin, BuildbotMixin,
         self.copyfile(src, dst)
         self.read_from_file(dst, verbose=True)
 
-    def _mach(self, target, env, halt_on_failure=True, output_parser=None):
-        dirs = self.query_abs_dirs()
-        mach = self._get_mach_executable()
-        return self.run_command(mach + target,
-                                halt_on_failure=True,
-                                env=env,
-                                cwd=dirs['abs_mozilla_dir'],
-                                output_parser=None)
-
     def _mach_configure(self):
         """calls mach configure"""
         env = self.query_bootstrap_env()
         target = ["configure"]
         return self._mach(target=target, env=env)
 
-    def _get_mach_executable(self):
-        python = self.query_exe('python2.7')
-        return [python, 'mach']
-
     def _get_make_executable(self):
         config = self.config
         dirs = self.query_abs_dirs()
diff --git a/toolkit/components/telemetry/Histograms.json b/toolkit/components/telemetry/Histograms.json
index caf4856cf94..c625becd8f0 100644
--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -8271,11 +8271,6 @@
     "releaseChannelCollection": "opt-out",
     "description": "Number of sessions where at least one chat message was exchanged"
   },
-  "E10S_AUTOSTART": {
-    "expires_in_version": "never",
-    "kind": "boolean",
-    "description": "Whether a session is set to autostart e10s windows"
-  },
   "E10S_AUTOSTART_STATUS": {
     "expires_in_version": "never",
     "kind": "enumerated",
diff --git a/toolkit/components/telemetry/TelemetryController.jsm b/toolkit/components/telemetry/TelemetryController.jsm
index 920de2503d0..61afcf8a6ae 100644
--- a/toolkit/components/telemetry/TelemetryController.jsm
+++ b/toolkit/components/telemetry/TelemetryController.jsm
@@ -746,6 +746,11 @@ var Impl = {
         // task to complete, but TelemetryStorage blocks on it during shutdown.
         TelemetryStorage.runCleanPingArchiveTask();
 
+        // Now that FHR/healthreporter is gone, make sure to remove FHR's DB from
+        // the profile directory. This is a temporary measure that we should drop
+        // in the future.
+        TelemetryStorage.removeFHRDatabase();
+
         this._delayedInitTaskDeferred.resolve();
       } catch (e) {
         this._delayedInitTaskDeferred.reject(e);
diff --git a/toolkit/components/telemetry/TelemetryStorage.jsm b/toolkit/components/telemetry/TelemetryStorage.jsm
index cf254477d5f..955fdcc5e59 100644
--- a/toolkit/components/telemetry/TelemetryStorage.jsm
+++ b/toolkit/components/telemetry/TelemetryStorage.jsm
@@ -20,6 +20,7 @@ Cu.import("resource://gre/modules/osfile.jsm", this);
 Cu.import("resource://gre/modules/Task.jsm", this);
 Cu.import("resource://gre/modules/TelemetryUtils.jsm", this);
 Cu.import("resource://gre/modules/Promise.jsm", this);
+Cu.import("resource://gre/modules/Preferences.jsm", this);
 
 const LOGGER_NAME = "Toolkit.Telemetry";
 const LOGGER_PREFIX = "TelemetryStorage::";
@@ -413,6 +414,15 @@ this.TelemetryStorage = {
     return TelemetryStorageImpl.loadPingFile(aFilePath);
   }),
 
+  /**
+   * Remove FHR database files. This is temporary and will be dropped in
+   * the future.
+   * @return {Promise} Resolved when the database files are deleted.
+   */
+  removeFHRDatabase: function() {
+    return TelemetryStorageImpl.removeFHRDatabase();
+  },
+
   /**
    * Only used in tests, builds an archived ping path from the ping metadata.
    * @param {String} aPingId The ping id.
@@ -1718,6 +1728,42 @@ var TelemetryStorageImpl = {
 
     return true;
   },
+
+  /**
+   * Remove FHR database files. This is temporary and will be dropped in
+   * the future.
+   * @return {Promise} Resolved when the database files are deleted.
+   */
+  removeFHRDatabase: Task.async(function*() {
+    this._log.trace("removeFHRDatabase");
+
+    // Let's try to remove the FHR DB with the default filename first.
+    const FHR_DB_DEFAULT_FILENAME = "healthreport.sqlite";
+
+    // Even if it's uncommon, there may be 2 additional files: - a "write ahead log"
+    // (-wal) file and a "shared memory file" (-shm). We need to remove them as well.
+    let FILES_TO_REMOVE = [
+      OS.Path.join(OS.Constants.Path.profileDir, FHR_DB_DEFAULT_FILENAME),
+      OS.Path.join(OS.Constants.Path.profileDir, FHR_DB_DEFAULT_FILENAME + "-wal"),
+      OS.Path.join(OS.Constants.Path.profileDir, FHR_DB_DEFAULT_FILENAME + "-shm"),
+    ];
+
+    // FHR could have used either the default DB file name or a custom one
+    // through this preference.
+    const FHR_DB_CUSTOM_FILENAME =
+      Preferences.get("datareporting.healthreport.dbName", undefined);
+    if (FHR_DB_CUSTOM_FILENAME) {
+      FILES_TO_REMOVE.push(
+        OS.Path.join(OS.Constants.Path.profileDir, FHR_DB_CUSTOM_FILENAME),
+        OS.Path.join(OS.Constants.Path.profileDir, FHR_DB_CUSTOM_FILENAME + "-wal"),
+        OS.Path.join(OS.Constants.Path.profileDir, FHR_DB_CUSTOM_FILENAME + "-shm"));
+    }
+
+    for (let f of FILES_TO_REMOVE) {
+      yield OS.File.remove(f, {ignoreAbsent: true})
+                   .catch(e => this._log.error("removeFHRDatabase - failed to remove " + f, e));
+    }
+  }),
 };
 
 ///// Utility functions
diff --git a/toolkit/components/telemetry/tests/unit/test_TelemetryController.js b/toolkit/components/telemetry/tests/unit/test_TelemetryController.js
index eaa70367dd8..7746408efbc 100644
--- a/toolkit/components/telemetry/tests/unit/test_TelemetryController.js
+++ b/toolkit/components/telemetry/tests/unit/test_TelemetryController.js
@@ -460,6 +460,54 @@ add_task(function* test_telemetryEnabledUnexpectedValue(){
                "False must disable Telemetry recording.");
 });
 
+add_task(function* test_telemetryCleanFHRDatabase(){
+  const FHR_DBNAME_PREF = "datareporting.healthreport.dbName";
+  const CUSTOM_DB_NAME = "unlikely.to.be.used.sqlite";
+  const DEFAULT_DB_NAME = "healthreport.sqlite";
+
+  // Check that we're able to remove a FHR DB with a custom name.
+  const CUSTOM_DB_PATHS = [
+    OS.Path.join(OS.Constants.Path.profileDir, CUSTOM_DB_NAME),
+    OS.Path.join(OS.Constants.Path.profileDir, CUSTOM_DB_NAME + "-wal"),
+    OS.Path.join(OS.Constants.Path.profileDir, CUSTOM_DB_NAME + "-shm"),
+  ];
+  Preferences.set(FHR_DBNAME_PREF, CUSTOM_DB_NAME);
+
+  // Write fake DB files to the profile directory.
+  for (let dbFilePath of CUSTOM_DB_PATHS) {
+    yield OS.File.writeAtomic(dbFilePath, "some data");
+  }
+
+  // Trigger the cleanup and check that the files were removed.
+  yield TelemetryStorage.removeFHRDatabase();
+  for (let dbFilePath of CUSTOM_DB_PATHS) {
+    Assert.ok(!(yield OS.File.exists(dbFilePath)), "The DB must not be on the disk anymore: " + dbFilePath);
+  }
+
+  // We should not break anything if there's no DB file.
+  yield TelemetryStorage.removeFHRDatabase();
+
+  // Check that we're able to remove a FHR DB with the default name.
+  Preferences.reset(FHR_DBNAME_PREF);
+
+  const DEFAULT_DB_PATHS = [
+    OS.Path.join(OS.Constants.Path.profileDir, DEFAULT_DB_NAME),
+    OS.Path.join(OS.Constants.Path.profileDir, DEFAULT_DB_NAME + "-wal"),
+    OS.Path.join(OS.Constants.Path.profileDir, DEFAULT_DB_NAME + "-shm"),
+  ];
+
+  // Write fake DB files to the profile directory.
+  for (let dbFilePath of DEFAULT_DB_PATHS) {
+    yield OS.File.writeAtomic(dbFilePath, "some data");
+  }
+
+  // Trigger the cleanup and check that the files were removed.
+  yield TelemetryStorage.removeFHRDatabase();
+  for (let dbFilePath of DEFAULT_DB_PATHS) {
+    Assert.ok(!(yield OS.File.exists(dbFilePath)), "The DB must not be on the disk anymore: " + dbFilePath);
+  }
+});
+
 add_task(function* stopServer(){
   yield PingServer.stop();
   do_test_finished();
diff --git a/toolkit/xre/nsAppRunner.cpp b/toolkit/xre/nsAppRunner.cpp
index e3e50393395..67741c85e53 100644
--- a/toolkit/xre/nsAppRunner.cpp
+++ b/toolkit/xre/nsAppRunner.cpp
@@ -4782,7 +4782,6 @@ mozilla::BrowserTabsRemoteAutostart()
     status = kE10sEnabledByUser;
   }
 
-  mozilla::Telemetry::Accumulate(mozilla::Telemetry::E10S_AUTOSTART, gBrowserTabsRemoteAutostart);
   mozilla::Telemetry::Accumulate(mozilla::Telemetry::E10S_AUTOSTART_STATUS, status);
   if (Preferences::GetBool("browser.enabledE10SFromPrompt", false)) {
     mozilla::Telemetry::Accumulate(mozilla::Telemetry::E10S_STILL_ACCEPTED_FROM_PROMPT,