diff --git a/browser/base/content/aboutRobots.css b/browser/base/content/aboutRobots.css
deleted file mode 100644
index 7b78d53290..0000000000
--- a/browser/base/content/aboutRobots.css
+++ /dev/null
@@ -1,3 +0,0 @@
-.title {
-  background-image: url("chrome://browser/content/aboutRobots-icon.png");
-}
diff --git a/browser/base/content/aboutRobots.js b/browser/base/content/aboutRobots.js
deleted file mode 100644
index 9b0dc3f1e0..0000000000
--- a/browser/base/content/aboutRobots.js
+++ /dev/null
@@ -1,11 +0,0 @@
-var buttonClicked = false;
-var button = document.getElementById("errorTryAgain");
-button.onclick = function() {
-  if (buttonClicked) {
-    button.style.visibility = "hidden";
-  } else {
-    var newLabel = button.getAttribute("label2");
-    button.textContent = newLabel;
-    buttonClicked = true;
-  }
-};
diff --git a/browser/base/content/aboutRobots.xhtml b/browser/base/content/aboutRobots.xhtml
deleted file mode 100644
index 97dc32053f..0000000000
--- a/browser/base/content/aboutRobots.xhtml
+++ /dev/null
@@ -1,62 +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/. -->
-
-<!DOCTYPE html>
-<html xmlns="http://www.w3.org/1999/xhtml">
-  <head>
-    <meta http-equiv="Content-Security-Policy" content="default-src chrome:" />
-    <title data-l10n-id="page-title"></title>
-    <link rel="stylesheet" href="chrome://global/skin/in-content/info-pages.css" media="all"/>
-    <link rel="icon" type="image/png" id="favicon" href="chrome://browser/content/robot.ico"/>
-    <link rel="stylesheet" href="chrome://browser/content/aboutRobots.css"/>
-    <linkset>
-      <link rel="localization" href="browser/aboutRobots.ftl"/>
-    </linkset>
-  </head>
-
-  <body>
-
-    <!-- PAGE CONTAINER (for styling purposes only) -->
-    <div class="container">
-
-      <!-- Error Title -->
-      <div class="title">
-        <h1 class="title-text" data-l10n-id="error-title-text"></h1>
-      </div>
-
-      <!-- LONG CONTENT (the section most likely to require scrolling) -->
-      <div class="description">
-
-        <!-- Short Description -->
-        <div>
-          <p id="errorShortDescText" data-l10n-id="error-short-desc-text"></p>
-        </div>
-
-        <!-- Long Description -->
-        <div>
-          <ul>
-            <li data-l10n-id="error-long-desc1"></li>
-            <li data-l10n-id="error-long-desc2"></li>
-            <li data-l10n-id="error-long-desc3"></li>
-            <li data-l10n-id="error-long-desc4"></li>
-          </ul>
-        </div>
-
-        <!-- Short Description -->
-        <div>
-          <small data-l10n-id="error-trailer-desc-text"></small>
-        </div>
-
-      </div>
-
-      <!-- Button -->
-      <div class="button-container">
-        <button id="errorTryAgain"
-                data-l10n-id="error-try-again"
-                data-l10n-attrs="label2"></button>
-      </div>
-    </div>
-  </body>
-  <script src="chrome://browser/content/aboutRobots.js"/>
-</html>
diff --git a/browser/base/content/browser-siteIdentity.js b/browser/base/content/browser-siteIdentity.js
index ac181b5232..fd5d16fdbf 100644
--- a/browser/base/content/browser-siteIdentity.js
+++ b/browser/base/content/browser-siteIdentity.js
@@ -50,7 +50,7 @@ var gIdentityHandler = {
    * RegExp used to decide if an about url should be shown as being part of
    * the browser UI.
    */
-  _secureInternalUIWhitelist: /^(?:accounts|addons|cache|config|crashes|customizing|downloads|healthreport|license|permissions|preferences|rights|sessionrestore|support|welcomeback)(?:[?#]|$)/i,
+  _secureInternalUIWhitelist: /^(?:accounts|addons|cache|config|crashes|customizing|downloads|healthreport|license|permissions|preferences|rights|sessionrestore|support)(?:[?#]|$)/i,
 
   get _isBroken() {
     return this._state & Ci.nsIWebProgressListener.STATE_IS_BROKEN;
diff --git a/browser/base/content/browser.js b/browser/base/content/browser.js
index 3cba56dcb0..bf30927b13 100644
--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -608,9 +608,7 @@ var gInitialPages = [
   "about:newtab",
   "about:home",
   "about:privatebrowsing",
-  "about:welcomeback",
   "about:sessionrestore",
-  "about:welcome",
   "about:newinstall",
 ];
 
diff --git a/browser/base/content/test/general/browser_testOpenNewRemoteTabsFromNonRemoteBrowsers.js b/browser/base/content/test/general/browser_testOpenNewRemoteTabsFromNonRemoteBrowsers.js
index 0b5c59be03..0817cdae86 100644
--- a/browser/base/content/test/general/browser_testOpenNewRemoteTabsFromNonRemoteBrowsers.js
+++ b/browser/base/content/test/general/browser_testOpenNewRemoteTabsFromNonRemoteBrowsers.js
@@ -3,7 +3,7 @@
  */
 
 const OPEN_LOCATION_PREF = "browser.link.open_newwindow";
-const NON_REMOTE_PAGE = "about:welcomeback";
+const NON_REMOTE_PAGE = "about:support";
 
 const { PrivateBrowsingUtils } = ChromeUtils.import(
   "resource://gre/modules/PrivateBrowsingUtils.jsm"
diff --git a/browser/base/jar.mn b/browser/base/jar.mn
index 30c6a8b093..f3177473bc 100644
--- a/browser/base/jar.mn
+++ b/browser/base/jar.mn
@@ -10,9 +10,6 @@ browser.jar:
         content/browser/aboutDialog.css               (content/aboutDialog.css)
         content/browser/aboutRestartRequired.js       (content/aboutRestartRequired.js)
         content/browser/aboutRestartRequired.xhtml    (content/aboutRestartRequired.xhtml)
-        content/browser/aboutRobots.xhtml             (content/aboutRobots.xhtml)
-        content/browser/aboutRobots.js                (content/aboutRobots.js)
-        content/browser/aboutRobots.css               (content/aboutRobots.css)
 
         content/browser/illustrations/error-connection-failure.svg (content/illustrations/error-connection-failure.svg)
         content/browser/illustrations/error-server-not-found.svg (content/illustrations/error-server-not-found.svg)
@@ -21,7 +18,6 @@ browser.jar:
         content/browser/illustrations/blue-berror.svg (content/illustrations/blue-berror.svg)
         content/browser/aboutNetError.xhtml            (content/aboutNetError.xhtml)
         content/browser/aboutNetError.js               (content/aboutNetError.js)
-        content/browser/aboutRobots-icon.png          (content/aboutRobots-icon.png)
         content/browser/aboutFrameCrashed.html        (content/aboutFrameCrashed.html)
         content/browser/aboutTabCrashed.css           (content/aboutTabCrashed.css)
         content/browser/aboutTabCrashed.js            (content/aboutTabCrashed.js)
diff --git a/browser/components/about/AboutRedirector.cpp b/browser/components/about/AboutRedirector.cpp
index 8dbf883e23..b10cf9aba8 100644
--- a/browser/components/about/AboutRedirector.cpp
+++ b/browser/components/about/AboutRedirector.cpp
@@ -70,13 +70,8 @@ static const RedirEntry kRedirMap[] = {
     {"rights", "chrome://global/content/aboutRights.xhtml",
      nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT |
          nsIAboutModule::ALLOW_SCRIPT},
-    {"robots", "chrome://browser/content/aboutRobots.xhtml",
-     nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT |
-         nsIAboutModule::ALLOW_SCRIPT},
     {"sessionrestore", "chrome://browser/content/aboutSessionRestore.xhtml",
      nsIAboutModule::ALLOW_SCRIPT | nsIAboutModule::HIDE_FROM_ABOUTABOUT},
-    {"welcomeback", "chrome://browser/content/aboutWelcomeBack.xhtml",
-     nsIAboutModule::ALLOW_SCRIPT | nsIAboutModule::HIDE_FROM_ABOUTABOUT},
     // Actual activity stream URL for home and newtab are set in channel
     // creation
     {"home", "about:blank", ACTIVITY_STREAM_FLAGS},
diff --git a/browser/components/about/components.conf b/browser/components/about/components.conf
index fcdb2f4ca7..45c5479838 100644
--- a/browser/components/about/components.conf
+++ b/browser/components/about/components.conf
@@ -18,11 +18,9 @@ pages = [
     'reader',
     'restartrequired',
     'rights',
-    'robots',
     'sessionrestore',
     'tabcrashed',
     'welcome',
-    'welcomeback',
 ]
 
 if defined('NIGHTLY_BUILD'):
diff --git a/browser/components/migration/content/aboutWelcomeBack.xhtml b/browser/components/migration/content/aboutWelcomeBack.xhtml
deleted file mode 100644
index 84ea1058a1..0000000000
--- a/browser/components/migration/content/aboutWelcomeBack.xhtml
+++ /dev/null
@@ -1,75 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!--
-# 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/.
--->
-<!DOCTYPE html [
-  <!ENTITY % htmlDTD PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "DTD/xhtml1-strict.dtd">
-  %htmlDTD;
-]>
-
-<html xmlns="http://www.w3.org/1999/xhtml" xmlns:xul="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
-  <head>
-    <title data-l10n-id="welcome-back-tab-title"></title>
-    <link rel="stylesheet" href="chrome://global/skin/in-content/info-pages.css" type="text/css" media="all"/>
-    <link rel="stylesheet" href="chrome://browser/skin/aboutWelcomeBack.css" type="text/css" media="all"/>
-    <link rel="icon" type="image/png" href="chrome://browser/skin/info.svg"/>
-    <link rel="localization" href="browser/aboutSessionRestore.ftl"/>
-    <link rel="localization" href="branding/brand.ftl"/>
-    <script src="chrome://browser/content/aboutSessionRestore.js"/>
-  </head>
-
-  <body>
-
-    <div class="container">
-
-      <div class="title">
-        <h1 class="title-text" data-l10n-id="welcome-back-page-title"></h1>
-      </div>
-
-      <div class="description">
-
-        <p data-l10n-id="welcome-back-page-info"></p>
-        <!-- Note a href in the anchor below is added by JS -->
-        <p data-l10n-id="welcome-back-page-info-link"><a id="linkMoreTroubleshooting" target="_blank" data-l10n-name="link-more"></a></p>
-
-        <div>
-          <div class="radioRestoreContainer">
-            <input class="radioRestoreButton" id="radioRestoreAll" type="radio"
-                   name="restore" checked="checked"/>
-            <label class="radioRestoreLabel" for="radioRestoreAll" data-l10n-id="welcome-back-restore-all-label"></label>
-          </div>
-
-          <div class="radioRestoreContainer">
-            <input class="radioRestoreButton" id="radioRestoreChoose" type="radio"
-                   name="restore"/>
-            <label class="radioRestoreLabel" for="radioRestoreChoose" data-l10n-id="welcome-back-restore-some-label"></label>
-          </div>
-        </div>
-      </div>
-
-      <div class="tree-container">
-        <xul:tree id="tabList" flex="1" seltype="single" hidecolumnpicker="true"
-                  onclick="onListClick(event);" onkeydown="onListKeyDown(event);">
-          <xul:treecols>
-            <xul:treecol cycler="true" id="restore" type="checkbox" data-l10n-id="restore-page-restore-header"/>
-            <xul:splitter class="tree-splitter"/>
-            <xul:treecol primary="true" id="title" data-l10n-id="restore-page-list-header" flex="1"/>
-          </xul:treecols>
-          <xul:treechildren flex="1"/>
-        </xul:tree>
-      </div>
-
-      <div class="button-container">
-        <xul:button class="primary"
-                    id="errorTryAgain"
-                    data-l10n-id="welcome-back-restore-button"
-                    oncommand="restoreSession();"/>
-      </div>
-
-      <input type="text" id="sessionData" style="display: none;"/>
-
-    </div>
-  </body>
-</html>
diff --git a/browser/components/migration/jar.mn b/browser/components/migration/jar.mn
index 23137ba7c5..b369ee1dcd 100644
--- a/browser/components/migration/jar.mn
+++ b/browser/components/migration/jar.mn
@@ -5,4 +5,3 @@
 browser.jar:
 *  content/browser/migration/migration.xul                    (content/migration.xul)
    content/browser/migration/migration.js                     (content/migration.js)
-   content/browser/aboutWelcomeBack.xhtml                     (content/aboutWelcomeBack.xhtml)
diff --git a/browser/components/migration/tests/marionette/test_refresh_firefox.py b/browser/components/migration/tests/marionette/test_refresh_firefox.py
index 6647be42cd..3120c6e3e8 100644
--- a/browser/components/migration/tests/marionette/test_refresh_firefox.py
+++ b/browser/components/migration/tests/marionette/test_refresh_firefox.py
@@ -346,7 +346,7 @@ def checkSession(self):
         tabURIs = self.runCode("""
           return [... gBrowser.browsers].map(b => b.currentURI && b.currentURI.spec)
         """)
-        self.assertSequenceEqual(tabURIs, ["about:welcomeback"])
+        self.assertSequenceEqual(tabURIs, ["about:welcome"])
 
         # Dismiss modal dialog if any. This is mainly to dismiss the check for
         # default browser dialog if it shows up.
diff --git a/browser/components/sessionstore/SessionMigration.jsm b/browser/components/sessionstore/SessionMigration.jsm
index 08e076e9c8..df14d99a62 100644
--- a/browser/components/sessionstore/SessionMigration.jsm
+++ b/browser/components/sessionstore/SessionMigration.jsm
@@ -66,7 +66,7 @@ var SessionMigrationInternal = {
       win._closedTabs = [];
       return win;
     });
-    let url = "about:welcomeback";
+    let url = "about:welcome";
     let formdata = { id: { sessionData: state }, url };
     let entry = {
       url,
diff --git a/browser/components/sessionstore/SessionStore.jsm b/browser/components/sessionstore/SessionStore.jsm
index 581c467026..30dbd8f12f 100644
--- a/browser/components/sessionstore/SessionStore.jsm
+++ b/browser/components/sessionstore/SessionStore.jsm
@@ -730,14 +730,6 @@ var SessionStoreInternal = {
                   E10SUtils.SERIALIZED_SYSTEMPRINCIPAL,
               };
               state = { windows: [{ tabs: [{ entries: [entry], formdata }] }] };
-            } else if (
-              this._hasSingleTabWithURL(state.windows, "about:welcomeback")
-            ) {
-              // On a single about:welcomeback URL that crashed, replace about:welcomeback
-              // with about:sessionrestore, to make clear to the user that we crashed.
-              state.windows[0].tabs[0].entries[0].url = "about:sessionrestore";
-              state.windows[0].tabs[0].entries[0].triggeringPrincipal_base64 =
-                E10SUtils.SERIALIZED_SYSTEMPRINCIPAL;
             }
           }
 
@@ -5288,8 +5280,7 @@ var SessionStoreInternal = {
 
     // don't wrap a single about:sessionrestore page
     if (
-      this._hasSingleTabWithURL(winData, "about:sessionrestore") ||
-      this._hasSingleTabWithURL(winData, "about:welcomeback")
+      this._hasSingleTabWithURL(winData, "about:sessionrestore")
     ) {
       return false;
     }
diff --git a/browser/locales/en-US/browser/aboutRobots.ftl b/browser/locales/en-US/browser/aboutRobots.ftl
deleted file mode 100644
index e5932fd2f3..0000000000
--- a/browser/locales/en-US/browser/aboutRobots.ftl
+++ /dev/null
@@ -1,28 +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/.
-
-### These strings are used in the about:robots page, which ties in with the
-### robots theme used in the Firefox 3 Beta 2/3 first run pages.
-### They're just meant to be fun and whimsical, with references to some geeky
-### but well-known robots in movies and books. Be creative with translations!
-
-# Nonsense line from the movie "The Day The Earth Stood Still". No translation needed.
-page-title = Gort! Klaatu barada nikto!
-# Movie: Logan's Run... Box (cyborg): "Welcome Humans! I am ready for you."
-error-title-text = Welcome Humans!
-# Movie: The Day The Earth Stood Still. Spoken by Klaatu.
-error-short-desc-text = We have come to visit you in peace and with goodwill!
-# Various books by Isaac Asimov. http://en.wikipedia.org/wiki/Three_Laws_of_Robotics
-error-long-desc1 = Robots may not injure a human being or, through inaction, allow a human being to come to harm.
-# Movie: Blade Runner. Batty: "I've seen things you people wouldn’t believe..."
-error-long-desc2 = Robots have seen things you people wouldn’t believe.
-# Book: Hitchhiker’s Guide To The Galaxy. What the Sirius Cybernetics Corporation calls robots.
-error-long-desc3 = Robots are Your Plastic Pal Who’s Fun To Be With.
-# TV: Futurama. Bender's first line is "Bite my shiny metal ass."
-error-long-desc4 = Robots have shiny metal posteriors which should not be bitten.
-# TV: Battlestar Galactica (2004 series). From the opening text.
-error-trailer-desc-text = And they have a plan.
-# Book: Hitchhiker's Guide To The Galaxy. Arthur presses a button and it warns him.
-error-try-again = Try Again
-    .label2 = Please do not press this button again.
diff --git a/browser/locales/en-US/browser/aboutSessionRestore.ftl b/browser/locales/en-US/browser/aboutSessionRestore.ftl
index 4572e2426c..9d087838fc 100644
--- a/browser/locales/en-US/browser/aboutSessionRestore.ftl
+++ b/browser/locales/en-US/browser/aboutSessionRestore.ftl
@@ -33,18 +33,3 @@ restore-page-try-again-button =
 restore-page-close-button =
     .label = Start New Session
     .accesskey = N
-
-## The following strings are used in about:welcomeback
-welcome-back-tab-title = Success!
-welcome-back-page-title = Success!
-welcome-back-page-info = { -brand-short-name } is ready to go.
-
-welcome-back-restore-button =
-    .label = Let’s go!
-    .accesskey = L
-
-welcome-back-restore-all-label = Restore all windows & tabs
-welcome-back-restore-some-label = Restore only the ones you want
-
-welcome-back-page-info-link = Your add-ons and customizations have been removed and your browser settings have been restored to their defaults. If this didn’t fix your issue, <a data-l10n-name="link-more">learn more about what you can do.</a>
-
diff --git a/browser/moz.configure b/browser/moz.configure
index 95a7ccc249..05e41cd3e0 100644
--- a/browser/moz.configure
+++ b/browser/moz.configure
@@ -3,7 +3,6 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 imply_option('MOZ_PLACES', True)
-imply_option('MOZ_SERVICES_HEALTHREPORT', True)
 imply_option('MOZ_SERVICES_SYNC', True)
 imply_option('MOZ_DEDICATED_PROFILES', True)
 imply_option('MOZ_BLOCK_PROFILE_DOWNGRADE', True)
diff --git a/browser/themes/shared/aboutWelcomeBack.css b/browser/themes/shared/aboutWelcomeBack.css
deleted file mode 100644
index b6a3e20e15..0000000000
--- a/browser/themes/shared/aboutWelcomeBack.css
+++ /dev/null
@@ -1,55 +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/. */
-
-.title {
-  background-image: url("chrome://browser/skin/welcome-back.svg");
-}
-
-.radioRestoreContainer:not(:last-child) {
-  margin-bottom: 0.2em;
-}
-
-/* tablist starts out hidden, but JS may make it visible in response to
-   clicks on the radio buttons by setting an "available" attribute.
-*/
-.tree-container:not([available]) {
-  display: none;
-}
-
-treechildren::-moz-tree-image(icon),
-treechildren::-moz-tree-image(noicon) {
-  padding-right: 2px;
-  margin: 0 2px;
-  width: 16px;
-  height: 16px;
-}
-
-treechildren::-moz-tree-image(noicon) {
-  list-style-image: url("chrome://mozapps/skin/places/defaultFavicon.svg");
-  -moz-context-properties: fill;
-  fill: currentColor;
-}
-treechildren::-moz-tree-image(container, noicon) {
-  list-style-image: url("chrome://browser/skin/window.svg");
-}
-
-treechildren::-moz-tree-image(checked) {
-  list-style-image: url("chrome://global/skin/icons/check.svg");
-  -moz-context-properties: fill, stroke;
-  fill: #2292d0;
-}
-treechildren::-moz-tree-image(checked, selected) {
-  fill: white;
-  stroke: #0095dd;
-}
-
-treechildren::-moz-tree-image(partial) {
-  list-style-image: url("chrome://global/skin/icons/check-partial.svg");
-  -moz-context-properties: fill, stroke;
-  fill: #2292d0;
-}
-treechildren::-moz-tree-image(partial, selected) {
-  fill: white;
-  stroke: #0095dd;
-}
diff --git a/browser/themes/shared/incontent-icons/welcome-back.svg b/browser/themes/shared/incontent-icons/welcome-back.svg
deleted file mode 100644
index 2fbea04b4e..0000000000
--- a/browser/themes/shared/incontent-icons/welcome-back.svg
+++ /dev/null
@@ -1,13 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<!-- 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/. -->
-<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 60 60">
-  <defs>
-    <linearGradient id="gradient" gradientUnits="userSpaceOnUse" x1="0" y1="30" x2="60" y2="30">
-      <stop offset="0" style="stop-color: #fd6b0c"/>
-      <stop offset="1" style="stop-color: #e65206"/>
-    </linearGradient>
-  </defs>
-  <path fill="url(#gradient)" d="M45.844,41.272c0.018-0.08,0.039-0.156,0.055-0.239c0.097-0.35,0.164-0.735,0.215-1.136 c0.375-0.835,0.747-2.172,0.5-3.936c-0.021-0.326-0.073-0.669-0.14-1.018c4.957-3.957,24.499-20.957,5.137-29.039 c0,0,4.23,6.9-2.898,13.92c-4.332,4.266-5.37,8.436-5.058,11.538c0,0,0.036,0.21,0.096,0.564c-1.62-2.178-5.652-4.53-14.256-2.022 c-8.736,2.544-7.476,4.518-9.234,3.606c0,0-0.93-2.166-3.564-4.452c0,0,0.726-4.416-0.42-5.472 c-1.146-1.062-2.628,2.244-5.346,3.432c-2.712,1.188-6.234,2.928-6.57,6.024l-3.39,2.328c0,0-1.446,0.684-0.81,1.32 c0.636,0.636,1.698,1.44,3.012,1.314c1.314-0.126,2.928-0.51,4.158-0.168c1.23,0.336,2.202,2.67,4.872,6.102 c0,0,2.142,4.542,6.936,5.412c0.036,0.024,0.072,0.054,0.108,0.078c1.404,1.026,4.584,3.336,5.148,3.834 c0.744,0.636,7.422,1.158,9.486,0.474c0,0-0.6-3.408-5.04-1.944c0,0-2.082,0.078-4.59-2.892c0.228-0.072,0.456-0.156,0.69-0.252 c1.056-0.402,2.184-0.966,3.39-1.728c0,0,1.542-0.774,3.846-1.356c0,0,2.497-0.555,4.376,0.455c2.542,1.829,6.483,2.442,12.58-0.566 c0,0,5.357,5.102,7.575,8.644c0,0,4.916-1.89-5.065-11.76C51.643,42.336,47.455,42.801,45.844,41.272z"/>
-</svg>
diff --git a/browser/themes/shared/jar.inc.mn b/browser/themes/shared/jar.inc.mn
index 4c4ccb28b8..409ef4e4e9 100644
--- a/browser/themes/shared/jar.inc.mn
+++ b/browser/themes/shared/jar.inc.mn
@@ -15,7 +15,6 @@
   skin/classic/browser/aboutLibrary.css                        (../shared/aboutLibrary.css)
   skin/classic/browser/aboutFrameCrashed.css                   (../shared/aboutFrameCrashed.css)
   skin/classic/browser/aboutTabCrashed.css                     (../shared/aboutTabCrashed.css)
-  skin/classic/browser/aboutWelcomeBack.css                    (../shared/aboutWelcomeBack.css)
   skin/classic/browser/setDesktopBackground.css                (../shared/setDesktopBackground.css)
   skin/classic/browser/addons/addon-install-blocked.svg        (../shared/addons/addon-install-blocked.svg)
   skin/classic/browser/addons/addon-install-confirm.svg        (../shared/addons/addon-install-confirm.svg)
@@ -249,7 +248,6 @@
   skin/classic/browser/cert-error.svg                          (../shared/incontent-icons/cert-error.svg)
   skin/classic/browser/wifi.svg                                (../shared/incontent-icons/wifi.svg)
   skin/classic/browser/tab-crashed.svg                         (../shared/incontent-icons/tab-crashed.svg)
-  skin/classic/browser/welcome-back.svg                        (../shared/incontent-icons/welcome-back.svg)
   skin/classic/browser/readerMode.svg                          (../shared/reader/readerMode.svg)
   skin/classic/browser/panic-panel/header.png                  (../shared/panic-panel/header.png)
   skin/classic/browser/panic-panel/header@2x.png               (../shared/panic-panel/header@2x.png)
diff --git a/docshell/base/nsAboutRedirector.cpp b/docshell/base/nsAboutRedirector.cpp
index f6542f161c..680040ba45 100644
--- a/docshell/base/nsAboutRedirector.cpp
+++ b/docshell/base/nsAboutRedirector.cpp
@@ -89,8 +89,6 @@ static const RedirEntry kRedirMap[] = {
          nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT |
          nsIAboutModule::URI_MUST_LOAD_IN_CHILD |
          nsIAboutModule::URI_CAN_LOAD_IN_PRIVILEGED_CHILD},
-    {"mozilla", "chrome://global/content/mozilla.xhtml",
-     nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT},
     {"neterror", "chrome://global/content/netError.xhtml",
      nsIAboutModule::URI_SAFE_FOR_UNTRUSTED_CONTENT |
          nsIAboutModule::URI_CAN_LOAD_IN_CHILD | nsIAboutModule::ALLOW_SCRIPT |
diff --git a/mobile/android/moz.configure b/mobile/android/moz.configure
index 63e0cc9c0f..50b000a5c0 100644
--- a/mobile/android/moz.configure
+++ b/mobile/android/moz.configure
@@ -120,7 +120,6 @@ def fennec_nightly(nightly):
     return bool(nightly)
 
 
-imply_option('MOZ_SERVICES_HEALTHREPORT', True)
 imply_option('MOZ_ANDROID_HISTORY', True)
 imply_option('--enable-small-chunk-size', True)
 
diff --git a/modules/libpref/init/StaticPrefList.yaml b/modules/libpref/init/StaticPrefList.yaml
index 571d097d5b..96ad2021f3 100644
--- a/modules/libpref/init/StaticPrefList.yaml
+++ b/modules/libpref/init/StaticPrefList.yaml
@@ -6218,12 +6218,6 @@
   value: false
   mirror: always
 
-# Telemetry of traffic categories. Whether or not to enable HttpTrafficAnalyzer.
-- name: network.traffic_analyzer.enabled
-  type: RelaxedAtomicBool
-  value: false
-  mirror: always
-
 - name: network.delay.tracking.load
   type: uint32_t
   value: 0
diff --git a/modules/libpref/init/all.js b/modules/libpref/init/all.js
index d512706e79..bceb6ca88e 100644
--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -2197,7 +2197,7 @@ pref("security.dialog_enable_delay", 1000);
 pref("security.notification_enable_delay", 500);
 
 #if defined(DEBUG) && !defined(ANDROID)
-  pref("csp.about_uris_without_csp", "blank,printpreview,srcdoc,about,addons,cache-entry,config,crashes,debugging,devtools,downloads,home,memory,networking,newtab,performance,plugins,policies,profiles,restartrequired,serviceworkers,sessionrestore,support,sync-log,telemetry,url-classifier,welcomeback");
+  pref("csp.about_uris_without_csp", "blank,printpreview,srcdoc,about,addons,cache-entry,config,crashes,debugging,devtools,downloads,home,memory,networking,newtab,performance,plugins,policies,profiles,restartrequired,serviceworkers,sessionrestore,support,sync-log,telemetry,url-classifier");
   // the following prefs are for testing purposes only.
   pref("csp.overrule_about_uris_without_csp_whitelist", false);
   pref("csp.skip_about_page_has_csp_assert", false);
diff --git a/netwerk/protocol/http/HttpTrafficAnalyzer.cpp b/netwerk/protocol/http/HttpTrafficAnalyzer.cpp
deleted file mode 100644
index 6add15d803..0000000000
--- a/netwerk/protocol/http/HttpTrafficAnalyzer.cpp
+++ /dev/null
@@ -1,254 +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/. */
-
-#include "HttpTrafficAnalyzer.h"
-#include "HttpLog.h"
-
-#include "mozilla/StaticPrefs_network.h"
-#include "mozilla/Telemetry.h"
-#include "mozilla/Unused.h"
-
-namespace mozilla {
-namespace net {
-
-#define DEFINE_CATEGORY(_name, _idx) NS_LITERAL_CSTRING("Y" #_idx "_" #_name),
-static const nsCString gKeyName[] = {
-#include "HttpTrafficAnalyzer.inc"
-};
-#undef DEFINE_CATEGORY
-
-#define DEFINE_CATEGORY(_name, _idx) \
-  Telemetry::LABELS_HTTP_TRAFFIC_ANALYSIS_3::Y##_idx##_##_name,
-static const Telemetry::LABELS_HTTP_TRAFFIC_ANALYSIS_3 gTelemetryLabel[] = {
-#include "HttpTrafficAnalyzer.inc"
-};
-#undef DEFINE_CATEGORY
-
-// ----------------------------------------------------
-// | Flags                           |   Load Type    |
-// ----------------------------------------------------
-// | nsIClassOfService::Leader       |       A        |
-// | w/o nsIRequest::LOAD_BACKGROUND |       B        |
-// | w/ nsIRequest::LOAD_BACKGROUND  |       C        |
-// ----------------------------------------------------
-// | Category                        | List Category  |
-// ----------------------------------------------------
-// | Basic Disconnected List         |       I        |
-// | Content                         |      II        |
-// | Fingerprinting                  |     III        |
-// ----------------------------------------------------
-// ====================================================
-// | Normal Mode                                      |
-// ----------------------------------------------------
-// | Y = 0 for system principals                      |
-// | Y = 1 for first party                            |
-// | Y = 2 for non-listed third party type            |
-// ----------------------------------------------------
-// |          \Y\          | Type A | Type B | Type C |
-// ----------------------------------------------------
-// | Category I            |    3   |    4   |    5   |
-// | Category II           |    6   |    7   |    8   |
-// | Category III          |    9   |   10   |   11   |
-// ====================================================
-// | Private Mode                                     |
-// ----------------------------------------------------
-// | Y = 12 for system principals                     |
-// | Y = 13 for first party                           |
-// | Y = 14 for non-listed third party type           |
-// ----------------------------------------------------
-// |          \Y\          | Type A | Type B | Type C |
-// ----------------------------------------------------
-// | Category I            |   15   |   16   |   17   |
-// | Category II           |   18   |   19   |   20   |
-// | Category III          |   21   |   22   |   23   |
-// ====================================================
-
-HttpTrafficCategory HttpTrafficAnalyzer::CreateTrafficCategory(
-    bool aIsPrivateMode, bool aIsSystemPrincipal, bool aIsThirdParty,
-    ClassOfService aClassOfService, TrackingClassification aClassification) {
-  uint8_t category = aIsPrivateMode ? 12 : 0;
-  if (aIsSystemPrincipal) {
-    MOZ_ASSERT_IF(!aIsPrivateMode,
-                  gKeyName[category].EqualsLiteral("Y0_N1Sys"));
-    MOZ_ASSERT_IF(aIsPrivateMode,
-                  gKeyName[category].EqualsLiteral("Y12_P1Sys"));
-    return static_cast<HttpTrafficCategory>(category);
-  }
-  ++category;
-
-  if (!aIsThirdParty) {
-    MOZ_ASSERT_IF(!aIsPrivateMode, gKeyName[category].EqualsLiteral("Y1_N1"));
-    MOZ_ASSERT_IF(aIsPrivateMode, gKeyName[category].EqualsLiteral("Y13_P1"));
-    return static_cast<HttpTrafficCategory>(category);
-  }
-
-  switch (aClassification) {
-    case TrackingClassification::eNone:
-      ++category;
-      MOZ_ASSERT_IF(!aIsPrivateMode,
-                    gKeyName[category].EqualsLiteral("Y2_N3Oth"));
-      MOZ_ASSERT_IF(aIsPrivateMode,
-                    gKeyName[category].EqualsLiteral("Y14_P3Oth"));
-      return static_cast<HttpTrafficCategory>(category);
-    case TrackingClassification::eBasic:
-      category += 2;
-      break;
-    case TrackingClassification::eContent:
-      category += 5;
-      break;
-    case TrackingClassification::eFingerprinting:
-      category += 8;
-      break;
-    default:
-      MOZ_ASSERT(false, "incorrect classification");
-      return HttpTrafficCategory::eInvalid;
-  }
-
-  switch (aClassOfService) {
-    case ClassOfService::eLeader:
-      MOZ_ASSERT_IF(
-          !aIsPrivateMode,
-          (aClassification == TrackingClassification::eBasic &&
-           gKeyName[category].EqualsLiteral("Y3_N3BasicLead")) ||
-              (aClassification == TrackingClassification::eContent &&
-               gKeyName[category].EqualsLiteral("Y6_N3ContentLead")) ||
-              (aClassification == TrackingClassification::eFingerprinting &&
-               gKeyName[category].EqualsLiteral("Y9_N3FpLead")));
-      MOZ_ASSERT_IF(
-          aIsPrivateMode,
-          (aClassification == TrackingClassification::eBasic &&
-           gKeyName[category].EqualsLiteral("Y15_P3BasicLead")) ||
-              (aClassification == TrackingClassification::eContent &&
-               gKeyName[category].EqualsLiteral("Y18_P3ContentLead")) ||
-              (aClassification == TrackingClassification::eFingerprinting &&
-               gKeyName[category].EqualsLiteral("Y21_P3FpLead")));
-      return static_cast<HttpTrafficCategory>(category);
-    case ClassOfService::eBackground:
-      ++category;
-
-      MOZ_ASSERT_IF(
-          !aIsPrivateMode,
-          (aClassification == TrackingClassification::eBasic &&
-           gKeyName[category].EqualsLiteral("Y4_N3BasicBg")) ||
-              (aClassification == TrackingClassification::eContent &&
-               gKeyName[category].EqualsLiteral("Y7_N3ContentBg")) ||
-              (aClassification == TrackingClassification::eFingerprinting &&
-               gKeyName[category].EqualsLiteral("Y10_N3FpBg")));
-      MOZ_ASSERT_IF(
-          aIsPrivateMode,
-          (aClassification == TrackingClassification::eBasic &&
-           gKeyName[category].EqualsLiteral("Y16_P3BasicBg")) ||
-              (aClassification == TrackingClassification::eContent &&
-               gKeyName[category].EqualsLiteral("Y19_P3ContentBg")) ||
-              (aClassification == TrackingClassification::eFingerprinting &&
-               gKeyName[category].EqualsLiteral("Y22_P3FpBg")));
-
-      return static_cast<HttpTrafficCategory>(category);
-    case ClassOfService::eOther:
-      category += 2;
-
-      MOZ_ASSERT_IF(
-          !aIsPrivateMode,
-          (aClassification == TrackingClassification::eBasic &&
-           gKeyName[category].EqualsLiteral("Y5_N3BasicOth")) ||
-              (aClassification == TrackingClassification::eContent &&
-               gKeyName[category].EqualsLiteral("Y8_N3ContentOth")) ||
-              (aClassification == TrackingClassification::eFingerprinting &&
-               gKeyName[category].EqualsLiteral("Y11_N3FpOth")));
-      MOZ_ASSERT_IF(
-          aIsPrivateMode,
-          (aClassification == TrackingClassification::eBasic &&
-           gKeyName[category].EqualsLiteral("Y17_P3BasicOth")) ||
-              (aClassification == TrackingClassification::eContent &&
-               gKeyName[category].EqualsLiteral("Y20_P3ContentOth")) ||
-              (aClassification == TrackingClassification::eFingerprinting &&
-               gKeyName[category].EqualsLiteral("Y23_P3FpOth")));
-
-      return static_cast<HttpTrafficCategory>(category);
-  }
-
-  MOZ_ASSERT(false, "incorrect class of service");
-  return HttpTrafficCategory::eInvalid;
-}
-
-nsresult HttpTrafficAnalyzer::IncrementHttpTransaction(
-    HttpTrafficCategory aCategory) {
-  MOZ_ASSERT(OnSocketThread(), "not on socket thread");
-  MOZ_ASSERT(StaticPrefs::network_traffic_analyzer_enabled());
-  MOZ_ASSERT(aCategory != HttpTrafficCategory::eInvalid, "invalid category");
-
-  LOG(("HttpTrafficAnalyzer::IncrementHttpTransaction [%s] [this=%p]\n",
-       gKeyName[aCategory].get(), this));
-
-  Telemetry::AccumulateCategoricalKeyed(NS_LITERAL_CSTRING("Transaction"),
-                                        gTelemetryLabel[aCategory]);
-  return NS_OK;
-}
-
-nsresult HttpTrafficAnalyzer::IncrementHttpConnection(
-    HttpTrafficCategory aCategory) {
-  MOZ_ASSERT(OnSocketThread(), "not on socket thread");
-  MOZ_ASSERT(StaticPrefs::network_traffic_analyzer_enabled());
-  MOZ_ASSERT(aCategory != HttpTrafficCategory::eInvalid, "invalid category");
-
-  LOG(("HttpTrafficAnalyzer::IncrementHttpConnection [%s] [this=%p]\n",
-       gKeyName[aCategory].get(), this));
-
-  Telemetry::AccumulateCategoricalKeyed(NS_LITERAL_CSTRING("Connection"),
-                                        gTelemetryLabel[aCategory]);
-  return NS_OK;
-}
-
-nsresult HttpTrafficAnalyzer::IncrementHttpConnection(
-    nsTArray<HttpTrafficCategory>&& aCategories) {
-  MOZ_ASSERT(OnSocketThread(), "not on socket thread");
-  MOZ_ASSERT(StaticPrefs::network_traffic_analyzer_enabled());
-  MOZ_ASSERT(!aCategories.IsEmpty(), "empty category");
-
-  nsTArray<HttpTrafficCategory> categories(std::move(aCategories));
-
-  LOG(("HttpTrafficAnalyzer::IncrementHttpConnection size=%" PRIuPTR
-       " [this=%p]\n",
-       categories.Length(), this));
-
-  // divide categories into 4 parts:
-  //   1) normal 1st-party (Y = 0)
-  //   2) normal 3rd-party (0 < Y < 11)
-  //   3) private 1st-party (Y = 11)
-  //   4) private 3rd-party (11 < Y < 22)
-  // Normal and private transaction should not share the same connection,
-  // and we choose 3rd-party prior than 1st-party.
-  HttpTrafficCategory best = categories[0];
-  if ((best == 0 || best == 11) && categories.Length() > 1) {
-    best = categories[1];
-  }
-  Unused << IncrementHttpConnection(best);
-
-  return NS_OK;
-}
-
-#define CLAMP_U32(num) \
-  Clamp<uint32_t>(num, 0, std::numeric_limits<uint32_t>::max())
-
-nsresult HttpTrafficAnalyzer::AccumulateHttpTransferredSize(
-    HttpTrafficCategory aCategory, uint64_t aBytesRead, uint64_t aBytesSent) {
-  MOZ_ASSERT(OnSocketThread(), "not on socket thread");
-  MOZ_ASSERT(StaticPrefs::network_traffic_analyzer_enabled());
-  MOZ_ASSERT(aCategory != HttpTrafficCategory::eInvalid, "invalid category");
-
-  LOG(("HttpTrafficAnalyzer::AccumulateHttpTransferredSize [%s] rb=%" PRIu64 " "
-       "sb=%" PRIu64 " [this=%p]\n",
-       gKeyName[aCategory].get(), aBytesRead, aBytesSent, this));
-
-  // Telemetry supports uint32_t only, and we send KB here.
-  auto total = CLAMP_U32((aBytesRead >> 10) + (aBytesSent >> 10));
-  if (aBytesRead || aBytesSent) {
-    Telemetry::ScalarAdd(Telemetry::ScalarID::NETWORKING_DATA_TRANSFERRED_V3_KB,
-                         NS_ConvertUTF8toUTF16(gKeyName[aCategory]), total);
-  }
-  return NS_OK;
-}
-
-}  // namespace net
-}  // namespace mozilla
diff --git a/netwerk/protocol/http/HttpTrafficAnalyzer.h b/netwerk/protocol/http/HttpTrafficAnalyzer.h
deleted file mode 100644
index ec7aa8ae33..0000000000
--- a/netwerk/protocol/http/HttpTrafficAnalyzer.h
+++ /dev/null
@@ -1,48 +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/. */
-
-#ifndef mozilla_netwerk_protocol_http_HttpTrafficAnalyzer_h
-#define mozilla_netwerk_protocol_http_HttpTrafficAnalyzer_h
-
-namespace mozilla {
-namespace net {
-
-#define DEFINE_CATEGORY(_name, _idx) e##_name = _idx##u,
-enum HttpTrafficCategory : uint8_t {
-#include "HttpTrafficAnalyzer.inc"
-  eInvalid = 255,
-};
-#undef DEFINE_CATEGORY
-
-class HttpTrafficAnalyzer final {
- public:
-  enum ClassOfService : uint8_t {
-    eLeader = 0,
-    eBackground = 1,
-    eOther = 255,
-  };
-
-  enum TrackingClassification : uint8_t {
-    eNone = 0,
-    eBasic = 1,
-    eContent = 2,
-    eFingerprinting = 3,
-  };
-
-  static HttpTrafficCategory CreateTrafficCategory(
-      bool aIsPrivateMode, bool aIsSystemPrincipal, bool aIsThirdParty,
-      ClassOfService aClassOfService, TrackingClassification aClassification);
-
-  nsresult IncrementHttpTransaction(HttpTrafficCategory aCategory);
-  nsresult IncrementHttpConnection(HttpTrafficCategory aCategory);
-  nsresult IncrementHttpConnection(nsTArray<HttpTrafficCategory>&& aCategories);
-  nsresult AccumulateHttpTransferredSize(HttpTrafficCategory aCategory,
-                                         uint64_t aBytesRead,
-                                         uint64_t aBytesSent);
-};
-
-}  // namespace net
-}  // namespace mozilla
-
-#endif  // mozilla_netwerk_protocol_http_HttpTrafficAnalyzer_h
diff --git a/netwerk/protocol/http/HttpTrafficAnalyzer.inc b/netwerk/protocol/http/HttpTrafficAnalyzer.inc
deleted file mode 100644
index 3311d33ee8..0000000000
--- a/netwerk/protocol/http/HttpTrafficAnalyzer.inc
+++ /dev/null
@@ -1,106 +0,0 @@
-// Type A) Parser blocking script loads will have an mContentPolicyType
-//         indicating a script load and a nsIClassOfService::Leader class of service.
-// Type B) I couldn’t find a class flag that corresponds to synchronous loads
-//         that block the load event, but I think a simple way to determine
-//         which ones they are is to examine whether the channel belongs to a
-//         load group and do not have a LOAD_BACKGROUND load flag.
-//         If that condition holds, then it is blocking the load event of some document.
-// Type C) I think a simple way to find channels that don’t block document loads
-//         (e.g. XHR and fetch) is to look for those which are in a load group
-//         and have a LOAD_BACKGROUND load flag.
-
-
-// Y=0 - all system principal connections.
-DEFINE_CATEGORY(N1Sys, 0)
-
-// Y=1 - all requests/connections/bytes that are first party.
-DEFINE_CATEGORY(N1, 1)
-
-// Y=2 - all requests/connections/bytes that are third party
-// but don’t fall into other categories
-DEFINE_CATEGORY(N3Oth, 2)
-
-// Y=3 - all requests/connections/bytes associated with third party loads that
-// match the Analytics/Social/Advertising (Basic) Category and have a load of type (A)
-DEFINE_CATEGORY(N3BasicLead, 3)
-
-// Y=4 - all requests/connections/bytes associated with third party loads that
-// match the Analytics/Social/Advertising (Basic) Category and have a load of type (B)
-DEFINE_CATEGORY(N3BasicBg, 4)
-
-// Y=5 - all requests/connections/bytes associated with third party loads that
-// match the Analytics/Social/Advertising (Basic) Category and have a load of type (C)
-DEFINE_CATEGORY(N3BasicOth, 5)
-
-// Y=6 - all requests/connections/bytes associated with third party loads that
-// match the Content Category and have a load of type (A)
-DEFINE_CATEGORY(N3ContentLead, 6)
-
-// Y=7 - all requests/connections/bytes associated with third party loads that
-// match the Content Category and have a load of type (B)
-DEFINE_CATEGORY(N3ContentBg, 7)
-
-// Y=8 - all requests/connections/bytes associated with third party loads that
-// match the Content Category and have a load of type (C)
-DEFINE_CATEGORY(N3ContentOth, 8)
-
-// Y=9 - all requests/connections/bytes associated with third party loads that
-// match the Fingerprinting Category and have a load of type (A)
-DEFINE_CATEGORY(N3FpLead, 9)
-
-// Y=10 - all requests/connections/bytes associated with third party loads that
-// match the Fingerprinting Category and have a load of type (B)
-DEFINE_CATEGORY(N3FpBg, 10)
-
-// Y=11 - all requests/connections/bytes associated with third party loads that
-// match the Fingerprinting Category and have a load of type (C)
-DEFINE_CATEGORY(N3FpOth, 11)
-
-// Y=12 - private mode system principal connections.
-DEFINE_CATEGORY(P1Sys, 12)
-
-// Y=13 - private mode and all requests/connections/bytes that are first party.
-DEFINE_CATEGORY(P1, 13)
-
-// Y=14 - private mode and all requests/connections/bytes that are third party
-// but don’t fall into other categories
-DEFINE_CATEGORY(P3Oth, 14)
-
-// Y=15 - private mode and all requests/connections/bytes associated with
-// third party loads that match the Analytics/Social/Advertising (Basic) Category
-// and have a load of type (A)
-DEFINE_CATEGORY(P3BasicLead, 15)
-
-// Y=16 - private mode and all requests/connections/bytes associated with
-// third party loads that match the Analytics/Social/Advertising (Basic) Category
-// and have a load of type (B)
-DEFINE_CATEGORY(P3BasicBg, 16)
-
-// Y=17 - private mode and all requests/connections/bytes associated with
-// third party loads that match the Analytics/Social/Advertising (Basic) Category
-// and have a load of type (C)
-DEFINE_CATEGORY(P3BasicOth, 17)
-
-// Y=18 - private mode and all requests/connections/bytes associated with
-// third party loads that match the Content Category and have a load of type (A)
-DEFINE_CATEGORY(P3ContentLead, 18)
-
-// Y=19 - private mode and all requests/connections/bytes associated with
-// third party loads that match the Content Category and have a load of type (B)
-DEFINE_CATEGORY(P3ContentBg, 19)
-
-// Y=20 - private mode and all requests/connections/bytes associated with
-// third party loads that match the Content Category and have a load of type (C)
-DEFINE_CATEGORY(P3ContentOth, 20)
-
-// Y=21 - private mode and all requests/connections/bytes associated with
-// third party loads that match the Fingerprinting Category and have a load of type (A)
-DEFINE_CATEGORY(P3FpLead, 21)
-
-// Y=22 - private mode and all requests/connections/bytes associated with
-// third party loads that match the Fingerprinting Category and have a load of type (B)
-DEFINE_CATEGORY(P3FpBg, 22)
-
-// Y=23 - private mode and all requests/connections/bytes associated with
-// third party loads that match the Fingerprinting Category and have a load of type (C)
-DEFINE_CATEGORY(P3FpOth, 23)
diff --git a/netwerk/protocol/http/moz.build b/netwerk/protocol/http/moz.build
index dee3064e4d..f34732deaa 100644
--- a/netwerk/protocol/http/moz.build
+++ b/netwerk/protocol/http/moz.build
@@ -82,7 +82,6 @@ UNIFIED_SOURCES += [
     'HttpChannelParent.cpp',
     'HttpChannelParentListener.cpp',
     'HttpInfo.cpp',
-    'HttpTrafficAnalyzer.cpp',
     'InterceptedChannel.cpp',
     'InterceptedHttpChannel.cpp',
     'nsCORSListenerProxy.cpp',
diff --git a/netwerk/protocol/http/nsAHttpConnection.h b/netwerk/protocol/http/nsAHttpConnection.h
index 01079be8eb..b8ef43a747 100644
--- a/netwerk/protocol/http/nsAHttpConnection.h
+++ b/netwerk/protocol/http/nsAHttpConnection.h
@@ -149,10 +149,6 @@ class nsAHttpConnection : public nsISupports {
 
   // A notification of the current active tab id change.
   virtual void TopLevelOuterContentWindowIdChanged(uint64_t windowId) = 0;
-
-  // categories set by nsHttpTransaction to identify how this connection is
-  // being used.
-  virtual void SetTrafficCategory(HttpTrafficCategory) = 0;
 };
 
 NS_DEFINE_STATIC_IID_ACCESSOR(nsAHttpConnection, NS_AHTTPCONNECTION_IID)
@@ -229,9 +225,6 @@ NS_DEFINE_STATIC_IID_ACCESSOR(nsAHttpConnection, NS_AHTTPCONNECTION_IID)
   }                                                                        \
   void SetSecurityCallbacks(nsIInterfaceRequestor* aCallbacks) override {  \
     if (fwdObject) (fwdObject)->SetSecurityCallbacks(aCallbacks);          \
-  }                                                                        \
-  void SetTrafficCategory(HttpTrafficCategory aCategory) override {        \
-    if (fwdObject) (fwdObject)->SetTrafficCategory(aCategory);             \
   }
 
 // ThrottleResponse deliberately ommited since we want different implementation
diff --git a/netwerk/protocol/http/nsHttpChannel.cpp b/netwerk/protocol/http/nsHttpChannel.cpp
index 23702b00d7..39a147a4e9 100644
--- a/netwerk/protocol/http/nsHttpChannel.cpp
+++ b/netwerk/protocol/http/nsHttpChannel.cpp
@@ -113,7 +113,6 @@
 #include "mozilla/net/CookieSettings.h"
 #include "mozilla/net/NeckoChannelParams.h"
 #include "mozilla/net/UrlClassifierFeatureFactory.h"
-#include "HttpTrafficAnalyzer.h"
 #include "mozilla/dom/CanonicalBrowsingContext.h"
 #include "mozilla/dom/WindowGlobalParent.h"
 
@@ -1267,13 +1266,11 @@ nsresult nsHttpChannel::SetupTransaction() {
 
   EnsureTopLevelOuterContentWindowId();
 
-  HttpTrafficCategory category = CreateTrafficCategory();
-
   nsCOMPtr<nsIAsyncInputStream> responseStream;
   rv = mTransaction->Init(
       mCaps, mConnectionInfo, &mRequestHead, mUploadStream, mReqContentLength,
       mUploadStreamHasHeaders, GetCurrentThreadEventTarget(), callbacks, this,
-      mTopLevelOuterContentWindowId, category, getter_AddRefs(responseStream));
+      mTopLevelOuterContentWindowId, getter_AddRefs(responseStream));
   if (NS_FAILED(rv)) {
     mTransaction = nullptr;
     return rv;
@@ -1289,54 +1286,6 @@ nsresult nsHttpChannel::SetupTransaction() {
   return rv;
 }
 
-HttpTrafficCategory nsHttpChannel::CreateTrafficCategory() {
-  MOZ_ASSERT(!mFirstPartyClassificationFlags ||
-             !mThirdPartyClassificationFlags);
-
-  if (!StaticPrefs::network_traffic_analyzer_enabled()) {
-    return HttpTrafficCategory::eInvalid;
-  }
-
-  HttpTrafficAnalyzer::ClassOfService cos;
-  {
-    if ((mClassOfService & nsIClassOfService::Leader) &&
-        mLoadInfo->GetExternalContentPolicyType() ==
-            nsIContentPolicy::TYPE_SCRIPT) {
-      cos = HttpTrafficAnalyzer::ClassOfService::eLeader;
-    } else if (mLoadFlags & nsIRequest::LOAD_BACKGROUND) {
-      cos = HttpTrafficAnalyzer::ClassOfService::eBackground;
-    } else {
-      cos = HttpTrafficAnalyzer::ClassOfService::eOther;
-    }
-  }
-
-  bool isThirdParty =
-      nsContentUtils::IsThirdPartyWindowOrChannel(nullptr, this, mURI);
-  HttpTrafficAnalyzer::TrackingClassification tc;
-  {
-    uint32_t flags = isThirdParty ? mThirdPartyClassificationFlags
-                                  : mFirstPartyClassificationFlags;
-
-    using CF = nsIHttpChannel::ClassificationFlags;
-    using TC = HttpTrafficAnalyzer::TrackingClassification;
-
-    if (flags & CF::CLASSIFIED_TRACKING_CONTENT) {
-      tc = TC::eContent;
-    } else if (flags & CF::CLASSIFIED_FINGERPRINTING_CONTENT) {
-      tc = TC::eFingerprinting;
-    } else if (flags & CF::CLASSIFIED_ANY_BASIC_TRACKING) {
-      tc = TC::eBasic;
-    } else {
-      tc = TC::eNone;
-    }
-  }
-
-  bool isSystemPrincipal = mLoadInfo->LoadingPrincipal() &&
-                           mLoadInfo->LoadingPrincipal()->IsSystemPrincipal();
-  return HttpTrafficAnalyzer::CreateTrafficCategory(
-      NS_UsePrivateBrowsing(this), isSystemPrincipal, isThirdParty, cos, tc);
-}
-
 enum class Report { Error, Warning };
 
 // Helper Function to report messages to the console when the loaded
diff --git a/netwerk/protocol/http/nsHttpChannel.h b/netwerk/protocol/http/nsHttpChannel.h
index 35e00895c5..6321b8acaf 100644
--- a/netwerk/protocol/http/nsHttpChannel.h
+++ b/netwerk/protocol/http/nsHttpChannel.h
@@ -447,8 +447,6 @@ class nsHttpChannel final : public HttpBaseChannel,
   MOZ_MUST_USE nsresult ContinueAsyncRedirectChannelToURI(nsresult rv);
   MOZ_MUST_USE nsresult OpenRedirectChannel(nsresult rv);
 
-  HttpTrafficCategory CreateTrafficCategory();
-
   /**
    * A function that takes care of reading STS and PKP headers and enforcing
    * STS and PKP load rules. After a secure channel is erected, STS and PKP
diff --git a/netwerk/protocol/http/nsHttpConnection.cpp b/netwerk/protocol/http/nsHttpConnection.cpp
index 45cbbbfb39..b350c800ac 100644
--- a/netwerk/protocol/http/nsHttpConnection.cpp
+++ b/netwerk/protocol/http/nsHttpConnection.cpp
@@ -159,13 +159,8 @@ nsHttpConnection::~nsHttpConnection() {
       auto total =
           Clamp<uint32_t>((mTotalBytesRead >> 10) + (mTotalBytesWritten >> 10),
                           0, std::numeric_limits<uint32_t>::max());
-      Telemetry::ScalarAdd(
-          Telemetry::ScalarID::NETWORKING_DATA_TRANSFERRED_CAPTIVE_PORTAL,
-          total);
     }
 
-    Telemetry::ScalarAdd(
-        Telemetry::ScalarID::NETWORKING_HTTP_CONNECTIONS_CAPTIVE_PORTAL, 1);
   }
 
   if (mForceSendTimer) {
@@ -987,14 +982,6 @@ void nsHttpConnection::Close(nsresult reason, bool aIsShutdown) {
     mForceSendTimer = nullptr;
   }
 
-  if (!mTrafficCategory.IsEmpty()) {
-    HttpTrafficAnalyzer* hta = gHttpHandler->GetHttpTrafficAnalyzer();
-    if (hta) {
-      hta->IncrementHttpConnection(std::move(mTrafficCategory));
-      MOZ_ASSERT(mTrafficCategory.IsEmpty());
-    }
-  }
-
   if (NS_FAILED(reason)) {
     if (mIdleMonitoring) EndIdleMonitoring();
 
@@ -2713,14 +2700,5 @@ bool nsHttpConnection::CanAcceptWebsocket() {
   return mSpdySession->CanAcceptWebsocket();
 }
 
-void nsHttpConnection::SetTrafficCategory(HttpTrafficCategory aCategory) {
-  MOZ_ASSERT(OnSocketThread(), "not on socket thread");
-  if (aCategory == HttpTrafficCategory::eInvalid ||
-      mTrafficCategory.Contains(aCategory)) {
-    return;
-  }
-  Unused << mTrafficCategory.AppendElement(aCategory);
-}
-
 }  // namespace net
 }  // namespace mozilla
diff --git a/netwerk/protocol/http/nsHttpConnection.h b/netwerk/protocol/http/nsHttpConnection.h
index a1097de5d7..d0ae70751a 100644
--- a/netwerk/protocol/http/nsHttpConnection.h
+++ b/netwerk/protocol/http/nsHttpConnection.h
@@ -16,7 +16,6 @@
 #include "mozilla/Mutex.h"
 #include "ARefBase.h"
 #include "TimingStruct.h"
-#include "HttpTrafficAnalyzer.h"
 
 #include "nsIAsyncInputStream.h"
 #include "nsIAsyncOutputStream.h"
@@ -251,8 +250,6 @@ class nsHttpConnection final : public nsAHttpSegmentReader,
   // HTTP/2 websocket support
   bool CanAcceptWebsocket();
 
-  void SetTrafficCategory(HttpTrafficCategory aCategory);
-
  private:
   // Value (set in mTCPKeepaliveConfig) indicates which set of prefs to use.
   enum TCPKeepaliveConfig {
@@ -439,7 +436,6 @@ class nsHttpConnection final : public nsAHttpSegmentReader,
   TimingStruct mBootstrappedTimings;
   bool mBootstrappedTimingsSet;
 
-  nsTArray<HttpTrafficCategory> mTrafficCategory;
   bool mThroughCaptivePortal;
 };
 
diff --git a/netwerk/protocol/http/nsHttpHandler.cpp b/netwerk/protocol/http/nsHttpHandler.cpp
index a9126e3724..ec8b406fd1 100644
--- a/netwerk/protocol/http/nsHttpHandler.cpp
+++ b/netwerk/protocol/http/nsHttpHandler.cpp
@@ -2678,15 +2678,5 @@ bool nsHttpHandler::IsSpdyBlacklisted(const nsHttpConnectionInfo* ci) {
   return mBlacklistedSpdyOrigins.Contains(ci->GetOrigin());
 }
 
-HttpTrafficAnalyzer* nsHttpHandler::GetHttpTrafficAnalyzer() {
-  MOZ_ASSERT(OnSocketThread(), "not on socket thread");
-
-  if (!StaticPrefs::network_traffic_analyzer_enabled()) {
-    return nullptr;
-  }
-
-  return &mHttpTrafficAnalyzer;
-}
-
 }  // namespace net
 }  // namespace mozilla
diff --git a/netwerk/protocol/http/nsHttpHandler.h b/netwerk/protocol/http/nsHttpHandler.h
index f2b2f150b9..e2674ae176 100644
--- a/netwerk/protocol/http/nsHttpHandler.h
+++ b/netwerk/protocol/http/nsHttpHandler.h
@@ -11,7 +11,6 @@
 #include "nsHttpAuthCache.h"
 #include "nsHttpConnectionMgr.h"
 #include "ASpdySession.h"
-#include "HttpTrafficAnalyzer.h"
 
 #include "mozilla/Mutex.h"
 #include "mozilla/StaticPtr.h"
@@ -454,8 +453,6 @@ class nsHttpHandler final : public nsIHttpProtocolHandler,
 
   bool DumpHpackTables() { return mDumpHpackTables; }
 
-  HttpTrafficAnalyzer* GetHttpTrafficAnalyzer();
-
   bool GetThroughCaptivePortal() { return mThroughCaptivePortal; }
 
  private:
@@ -704,8 +701,6 @@ class nsHttpHandler final : public nsIHttpProtocolHandler,
   // If true, the transactions from active tab will be dispatched first.
   bool mActiveTabPriority;
 
-  HttpTrafficAnalyzer mHttpTrafficAnalyzer;
-
  private:
   // For Rate Pacing Certain Network Events. Only assign this pointer on
   // socket thread.
diff --git a/netwerk/protocol/http/nsHttpTransaction.cpp b/netwerk/protocol/http/nsHttpTransaction.cpp
index 3b15e89192..873e6375c0 100644
--- a/netwerk/protocol/http/nsHttpTransaction.cpp
+++ b/netwerk/protocol/http/nsHttpTransaction.cpp
@@ -126,8 +126,7 @@ nsHttpTransaction::nsHttpTransaction()
       m0RTTInProgress(false),
       mDoNotTryEarlyData(false),
       mEarlyDataDisposition(EARLY_NONE),
-      mFastOpenStatus(TFO_NOT_TRIED),
-      mTrafficCategory(HttpTrafficCategory::eInvalid) {
+      mFastOpenStatus(TFO_NOT_TRIED) {
   this->mSelfAddr.inet = {};
   this->mPeerAddr.inet = {};
   LOG(("Creating nsHttpTransaction @%p\n", this));
@@ -245,8 +244,7 @@ nsresult nsHttpTransaction::Init(
     nsIInputStream* requestBody, uint64_t requestContentLength,
     bool requestBodyHasHeaders, nsIEventTarget* target,
     nsIInterfaceRequestor* callbacks, nsITransportEventSink* eventsink,
-    uint64_t topLevelOuterContentWindowId, HttpTrafficCategory trafficCategory,
-    nsIAsyncInputStream** responseBody) {
+    uint64_t topLevelOuterContentWindowId, nsIAsyncInputStream** responseBody) {
   nsresult rv;
 
   LOG1(("nsHttpTransaction::Init [this=%p caps=%x]\n", this, caps));
@@ -259,8 +257,6 @@ nsresult nsHttpTransaction::Init(
   mTopLevelOuterContentWindowId = topLevelOuterContentWindowId;
   LOG(("  window-id = %" PRIx64, mTopLevelOuterContentWindowId));
 
-  mTrafficCategory = trafficCategory;
-
   mActivityDistributor = services::GetActivityDistributor();
   if (!mActivityDistributor) {
     return NS_ERROR_NOT_AVAILABLE;
@@ -520,16 +516,6 @@ void nsHttpTransaction::OnActivated() {
     return;
   }
 
-  if (mTrafficCategory != HttpTrafficCategory::eInvalid) {
-    HttpTrafficAnalyzer* hta = gHttpHandler->GetHttpTrafficAnalyzer();
-    if (hta) {
-      hta->IncrementHttpTransaction(mTrafficCategory);
-    }
-    if (mConnection) {
-      mConnection->SetTrafficCategory(mTrafficCategory);
-    }
-  }
-
   if (mConnection && mRequestHead &&
       mConnection->Version() >= HttpVersion::v2_0) {
     // So this is fun. On http/2, we want to send TE: Trailers, to be
@@ -1194,19 +1180,6 @@ void nsHttpTransaction::Close(nsresult reason) {
     }
   }
 
-  if (mTrafficCategory != HttpTrafficCategory::eInvalid) {
-    HttpTrafficAnalyzer* hta = gHttpHandler->GetHttpTrafficAnalyzer();
-    if (hta) {
-      hta->AccumulateHttpTransferredSize(mTrafficCategory, mTransferSize,
-                                         mContentRead);
-    }
-  }
-
-  if (mThroughCaptivePortal) {
-    Telemetry::ScalarAdd(
-        Telemetry::ScalarID::NETWORKING_HTTP_TRANSACTIONS_CAPTIVE_PORTAL, 1);
-  }
-
   if (relConn && mConnection) {
     MutexAutoLock lock(mLock);
     mConnection = nullptr;
diff --git a/netwerk/protocol/http/nsHttpTransaction.h b/netwerk/protocol/http/nsHttpTransaction.h
index 1dca1a3874..8002938ba3 100644
--- a/netwerk/protocol/http/nsHttpTransaction.h
+++ b/netwerk/protocol/http/nsHttpTransaction.h
@@ -85,7 +85,7 @@ class nsHttpTransaction final : public nsAHttpTransaction,
        uint64_t reqContentLength, bool reqBodyIncludesHeaders,
        nsIEventTarget* consumerTarget, nsIInterfaceRequestor* callbacks,
        nsITransportEventSink* eventsink, uint64_t topLevelOuterContentWindowId,
-       HttpTrafficCategory trafficCategory, nsIAsyncInputStream** responseBody);
+       nsIAsyncInputStream** responseBody);
 
   void OnActivated() override;
 
@@ -484,7 +484,6 @@ class nsHttpTransaction final : public nsAHttpTransaction,
   // H2 websocket support
   RefPtr<SpdyConnectTransaction> mH2WSTransaction;
 
-  HttpTrafficCategory mTrafficCategory;
   bool mThroughCaptivePortal;
 };
 
diff --git a/toolkit/components/telemetry/Histograms.json b/toolkit/components/telemetry/Histograms.json
index 638b21c24e..2a9d4525ef 100644
--- a/toolkit/components/telemetry/Histograms.json
+++ b/toolkit/components/telemetry/Histograms.json
@@ -13998,45 +13998,5 @@
       ],
       "keyed": true,
       "description": "Getting the number of errors in QuotaManager initialization."
-  },
-  "HTTP_TRAFFIC_ANALYSIS_3": {
-    "record_in_processes": ["main"],
-    "alert_emails": ["gachen@mozilla.com"],
-    "bug_numbers": [1533363, 1546796, 1546906, 1550756],
-    "expires_in_version": "73",
-    "kind": "categorical",
-    "n_values": 50,
-    "labels": [
-      "Y0_N1Sys",
-      "Y1_N1",
-      "Y2_N3Oth",
-      "Y3_N3BasicLead",
-      "Y4_N3BasicBg",
-      "Y5_N3BasicOth",
-      "Y6_N3ContentLead",
-      "Y7_N3ContentBg",
-      "Y8_N3ContentOth",
-      "Y9_N3FpLead",
-      "Y10_N3FpBg",
-      "Y11_N3FpOth",
-      "Y12_P1Sys",
-      "Y13_P1",
-      "Y14_P3Oth",
-      "Y15_P3BasicLead",
-      "Y16_P3BasicBg",
-      "Y17_P3BasicOth",
-      "Y18_P3ContentLead",
-      "Y19_P3ContentBg",
-      "Y20_P3ContentOth",
-      "Y21_P3FpLead",
-      "Y22_P3FpBg",
-      "Y23_P3FpOth"
-    ],
-    "keyed": true,
-    "keys": [
-      "Connection",
-      "Transaction"
-    ],
-    "description": "Numbers of HTTP transactions and connections by type. There are some categories separated by labels based on 5 parameters: 1. normal browsing or private browsing 2. system principal or not 3. first party or third party 4. class of service (Leader/Background/Others) 5. tracking classification (Basic/Content/FingerprintingContent)."
   }
 }
diff --git a/toolkit/components/telemetry/Scalars.yaml b/toolkit/components/telemetry/Scalars.yaml
index eacd21e488..b98f12307b 100644
--- a/toolkit/components/telemetry/Scalars.yaml
+++ b/toolkit/components/telemetry/Scalars.yaml
@@ -3387,112 +3387,6 @@ script.preloader:
       - 'main'
       - 'content'
 
-networking:
-  data_transferred_v3_kb:
-    bug_numbers:
-      - 1533363
-      - 1546903
-      - 1546796
-      - 1546906
-      - 1550756
-    description: >
-      How many KB of HTTP data transferred by type, there are some categories
-      separated by keys based on 5 parameters:
-        1. normal browsing or private browsing
-        2. system principal or not
-        3. first party or third party
-        4. class of service (Leader/Background/Others)
-        5. tracking classification (Basic/Content/FingerprintingContent)
-
-      Available keys are:
-        "Y0_N1Sys",
-        "Y1_N1",
-        "Y2_N3Oth",
-        "Y3_N3BasicLead",
-        "Y4_N3BasicBg",
-        "Y5_N3BasicOth",
-        "Y6_N3ContentLead",
-        "Y7_N3ContentBg",
-        "Y8_N3ContentOth",
-        "Y9_N3FpLead",
-        "Y10_N3FpBg",
-        "Y11_N3FpOth",
-        "Y12_P1Sys",
-        "Y13_P1",
-        "Y14_P3Oth",
-        "Y15_P3BasicLead",
-        "Y16_P3BasicBg",
-        "Y17_P3BasicOth",
-        "Y18_P3ContentLead",
-        "Y19_P3ContentBg",
-        "Y20_P3ContentOth",
-        "Y21_P3FpLead",
-        "Y22_P3FpBg",
-        "Y23_P3FpOth"
-    expires: "73"
-    keyed: true
-    kind: uint
-    notification_emails:
-      - gachen@mozilla.com
-    record_in_processes:
-      - 'main'
-
-  data_transferred_captive_portal:
-    bug_numbers:
-      - 1543005
-    description: >
-      Hom many KB has been transfer over a captive portal during a subsession.
-    expires: "73"
-    keyed: false
-    kind: uint
-    notification_emails:
-      - ddamjanovic@mozilla.com
-    record_in_processes:
-      - 'main'
-
-  http_transactions_captive_portal:
-    bug_numbers:
-      - 1543005
-    description: >
-      Number of http transactions transfer over a captive portal during a subsession.
-    expires: "73"
-    keyed: false
-    kind: uint
-    notification_emails:
-      - ddamjanovic@mozilla.com
-    record_in_processes:
-      - 'main'
-
-  http_connections_captive_portal:
-    bug_numbers:
-      - 1543005
-    description: >
-      Number of http connections transfer over a captive portal during a subsession.
-    expires: "73"
-    keyed: false
-    kind: uint
-    notification_emails:
-      - ddamjanovic@mozilla.com
-    record_in_processes:
-      - 'main'
-
-policies:
-  count:
-    bug_numbers:
-      - 1432897
-    description: >-
-      A uint with the number of active enterprise policies, collected once at
-      startup.
-    expires: never
-    kind: uint
-    notification_emails:
-      - mkaply@mozilla.com
-    release_channel_collection: opt-out
-    products:
-      - 'firefox'
-    record_in_processes:
-      - main
-
 # The following section is for probes testing the Telemetry system. They will not be
 # submitted in pings and are only used for testing.
 telemetry.test:
diff --git a/toolkit/content/jar.mn b/toolkit/content/jar.mn
index ed63fa2696..6859437d90 100644
--- a/toolkit/content/jar.mn
+++ b/toolkit/content/jar.mn
@@ -46,7 +46,6 @@ toolkit.jar:
    content/global/filepicker.properties
    content/global/customElements.js
    content/global/globalOverlay.js
-   content/global/mozilla.xhtml
    content/global/aboutMozilla.css
    content/global/preferencesBindings.js
    content/global/process-content.js
diff --git a/toolkit/content/mozilla.xhtml b/toolkit/content/mozilla.xhtml
deleted file mode 100644
index be331a6604..0000000000
--- a/toolkit/content/mozilla.xhtml
+++ /dev/null
@@ -1,34 +0,0 @@
-<!DOCTYPE html
-[
-  <!ENTITY % mozillaDTD SYSTEM "chrome://global/locale/mozilla.dtd" >
-  %mozillaDTD;
-  <!ENTITY % directionDTD SYSTEM "chrome://global/locale/global.dtd" >
-  %directionDTD;
-]>
-
-<!-- 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/. -->
-
-<html xmlns="http://www.w3.org/1999/xhtml">
-  <head>
-    <meta http-equiv="Content-Security-Policy" content="default-src 'none'; style-src chrome:" />
-    <meta charset='utf-8' />
-    <title>&mozilla.title.11.14;</title>
-    <link rel="stylesheet" href="chrome://global/content/aboutMozilla.css"/>" type="text/css"/>
-</head>
-
-<body dir="&locale.dir;">
-
-<section>
-  <p id="moztext">
-  &mozilla.quote.11.14;
-  </p>
-
-  <p id="from">
-  &mozilla.from.11.14;
-  </p>
-</section>
-
-</body>
-</html>
diff --git a/toolkit/locales/en-US/chrome/global/mozilla.dtd b/toolkit/locales/en-US/chrome/global/mozilla.dtd
deleted file mode 100644
index 49276f0815..0000000000
--- a/toolkit/locales/en-US/chrome/global/mozilla.dtd
+++ /dev/null
@@ -1,15 +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/. -->
-
-<!ENTITY mozilla.title.11.14
-'The Book of Mozilla, 11:14'>
-
-<!ENTITY mozilla.quote.11.14
-'The Beast adopted <em>new raiment</em> and studied the ways of <em>Time</em> and <em>Space</em> 
-and <em>Light</em> and the <em>Flow</em> of energy through the Universe. From its studies, 
-the Beast fashioned new structures from <em>oxidised metal</em> and proclaimed their glories. 
-And the Beast’s followers rejoiced, finding renewed purpose in these <em>teachings</em>.'>
-
-<!ENTITY mozilla.from.11.14
-'from <strong>The Book of Mozilla,</strong> 11:14'>
diff --git a/toolkit/locales/jar.mn b/toolkit/locales/jar.mn
index 1e8f1e767e..8e000920dc 100644
--- a/toolkit/locales/jar.mn
+++ b/toolkit/locales/jar.mn
@@ -36,7 +36,6 @@
   locale/@AB_CD@/global/intl.css                        (%chrome/global/intl.css)
   locale/@AB_CD@/global/intl.properties                 (%chrome/global/intl.properties)
   locale/@AB_CD@/global/keys.properties                 (%chrome/global/keys.properties)
-  locale/@AB_CD@/global/mozilla.dtd                     (%chrome/global/mozilla.dtd)
 #ifndef MOZ_FENNEC
   locale/@AB_CD@/global/narrate.properties              (%chrome/global/narrate.properties)
 #endif
