--- a/browser/base/content/browser-sets.inc
+++ b/browser/base/content/browser-sets.inc
@@ -43,7 +43,6 @@
     <command id="View:PageSource" oncommand="BrowserViewSource(window.gBrowser.selectedBrowser);" observes="canViewSource"/>
     <command id="View:PageInfo" oncommand="BrowserPageInfo();"/>
     <command id="View:FullScreen" oncommand="BrowserFullScreen();"/>
-    <command id="View:ReaderView" oncommand="ReaderParent.toggleReaderMode(event);"/>
     <command id="cmd_find"
              oncommand="gFindBar.onFindCommand();"
              observes="isImage"/>
@@ -281,7 +280,6 @@
     <key id="key_fullScreen_old" key="&fullScreenCmd.macCommandKey;" command="View:FullScreen" modifiers="accel,shift"/>
     <key keycode="VK_F11" command="View:FullScreen"/>
 #endif
-    <key id="key_toggleReaderMode" key="&toggleReaderMode.key;" command="View:ReaderView" modifiers="accel,alt" disabled="true"/>
     <key key="&reloadCmd.commandkey;" command="Browser:Reload" modifiers="accel" id="key_reload"/>
     <key key="&reloadCmd.commandkey;" command="Browser:ReloadSkipCache" modifiers="accel,shift"/>
     <key id="key_viewSource" key="&pageSourceCmd.commandkey;" command="View:PageSource" modifiers="accel"/>
--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -46,8 +46,6 @@
   PrivateBrowsingUtils: "resource://gre/modules/PrivateBrowsingUtils.jsm",
   ProcessHangMonitor: "resource:///modules/ProcessHangMonitor.jsm",
   PromiseUtils: "resource://gre/modules/PromiseUtils.jsm",
-  ReaderMode: "resource://gre/modules/ReaderMode.jsm",
-  ReaderParent: "resource:///modules/ReaderParent.jsm",
   RecentWindow: "resource:///modules/RecentWindow.jsm",
   SafeBrowsing: "resource://gre/modules/SafeBrowsing.jsm",
   SessionStore: "resource:///modules/sessionstore/SessionStore.jsm",
@@ -4753,7 +4751,6 @@
       }
     }
     UpdateBackForwardCommands(gBrowser.webNavigation);
-    ReaderParent.updateReaderButton(gBrowser.selectedBrowser);
 
     if (!gMultiProcessBrowser) // Bug 1108553 - Cannot rotate images with e10s
       gGestureSupport.restoreRotationState();
@@ -5122,8 +5119,8 @@
         aRequest.originalURI &&
         (aRequest.originalURI.schemeIs("chrome") ||
          (aRequest.originalURI.schemeIs("about") &&
-          aWebProgress.isTopLevel &&
-          !aRequest.originalURI.spec.startsWith("about:reader")))) {
+          aWebProgress.isTopLevel
+          ))) {
       return false;
     }
 
@@ -5195,9 +5192,6 @@
     // Filter out location changes caused by anchor navigation
     // or history.push/pop/replaceState.
     if (aFlags & Ci.nsIWebProgressListener.LOCATION_CHANGE_SAME_DOCUMENT) {
-      // Reader mode actually cares about these:
-      let mm = gBrowser.selectedBrowser.messageManager;
-      mm.sendAsyncMessage("Reader:PushState", {isArticle: gBrowser.selectedBrowser.isArticle});
       return;
     }
 
--- a/browser/base/content/browser.xul
+++ b/browser/base/content/browser.xul
@@ -876,11 +876,6 @@
                        hidden="true"
                        tooltiptext="&pageReportIcon.tooltip;"
                        onmousedown="gPopupBlockerObserver.onReportButtonMousedown(event);"/>
-                <image id="reader-mode-button"
-                       class="urlbar-icon urlbar-page-action"
-                       role="button"
-                       hidden="true"
-                       onclick="ReaderParent.buttonClick(event);"/>
                 <toolbarbutton id="urlbar-zoom-button"
                        onclick="FullZoom.reset();"
                        tooltip="dynamic-shortcut-tooltip"
--- a/browser/components/nsBrowserGlue.js
+++ b/browser/components/nsBrowserGlue.js
@@ -55,7 +55,6 @@
   PluralForm: "resource://gre/modules/PluralForm.jsm",
   PrivateBrowsingUtils: "resource://gre/modules/PrivateBrowsingUtils.jsm",
   ProcessHangMonitor: "resource:///modules/ProcessHangMonitor.jsm",
-  ReaderParent: "resource:///modules/ReaderParent.jsm",
   RecentWindow: "resource:///modules/RecentWindow.jsm",
   RemotePrompt: "resource:///modules/RemotePrompt.jsm",
   SafeBrowsing: "resource://gre/modules/SafeBrowsing.jsm",
@@ -145,9 +144,6 @@
     "FormValidation:ShowPopup": ["FormValidationHandler"],
     "FormValidation:HidePopup": ["FormValidationHandler"],
     "Prompt:Open": ["RemotePrompt"],
-    "Reader:ArticleGet": ["ReaderParent"],
-    "Reader:FaviconRequest": ["ReaderParent"],
-    "Reader:UpdateReaderButton": ["ReaderParent"],
     // PLEASE KEEP THIS LIST IN SYNC WITH THE MOBILE LISTENERS IN BrowserCLH.js
     "RemoteLogins:findLogins": ["LoginManagerParent"],
     "RemoteLogins:findRecipes": ["LoginManagerParent"],
--- a/browser/components/uitour/UITour.jsm
+++ b/browser/components/uitour/UITour.jsm
@@ -30,8 +30,6 @@
   "resource://gre/modules/PrivateBrowsingUtils.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "ProfileAge",
   "resource://gre/modules/ProfileAge.jsm");
-XPCOMUtils.defineLazyModuleGetter(this, "ReaderParent",
-  "resource:///modules/ReaderParent.jsm");
 XPCOMUtils.defineLazyModuleGetter(this, "PageActions",
   "resource:///modules/PageActions.jsm");
 
@@ -40,7 +38,6 @@
 const PREF_SEENPAGEIDS    = "browser.uitour.seenPageIDs";
 
 const BACKGROUND_PAGE_ACTIONS_ALLOWED = new Set([
-  "forceShowReaderIcon",
   "getConfiguration",
   "getTreatmentTag",
   "hideHighlight",
@@ -164,7 +161,6 @@
     }],
     ["privateWindow", {query: "#appMenu-private-window-button"}],
     ["quit",        {query: "#appMenu-quit-button"}],
-    ["readerMode-urlBar", {query: "#reader-mode-button"}],
     ["search",      {
       infoPanelOffsetX: 18,
       infoPanelPosition: "after_start",
@@ -653,15 +649,10 @@
       }
 
       case "forceShowReaderIcon": {
-        ReaderParent.forceShowReaderIcon(browser);
         break;
       }
 
       case "toggleReaderMode": {
-        let targetPromise = this.getTarget(window, "readerMode-urlBar");
-        targetPromise.then(target => {
-          ReaderParent.toggleReaderMode({target: target.node});
-        });
         break;
       }

--- a/browser/components/uitour/UITour-lib.js
+++ b/browser/components/uitour/UITour-lib.js
@@ -119,7 +119,6 @@
    * <li>pocket
    * <li>privateWindow
    * <li>quit
-   * <li>readerMode-urlBar
    * <li>screenshots
    * <li>search
    * <li>searchIcon
@@ -704,26 +703,6 @@
   };
 
   /**
-   * @summary Force the reader mode icon to appear in the address bar regardless of whether
-   * heuristics determine it's appropriate.
-   *
-   * @description This is useful if you want to target an annotation (panel/highlight) on it
-   * but the tour page doesn't have much textual content.
-   */
-  Mozilla.UITour.forceShowReaderIcon = function() {
-    _sendEvent("forceShowReaderIcon");
-  };
-
-  /**
-   * Toggle into reader mode for the current tab. Once the user enters reader
-   * mode, the UITour document will not be active and therefore cannot call other
-   * UITour APIs.
-   */
-  Mozilla.UITour.toggleReaderMode = function() {
-    _sendEvent("toggleReaderMode");
-  };
-
-  /**
    * @param {String} pane - Pane to open/switch the preferences to.
    * Valid values match fragments on about:preferences and are subject to change e.g.:
    *
--- a/browser/components/uitour/test/browser_UITour_toggleReaderMode.js
+++ b/browser/components/uitour/test/browser_UITour_toggleReaderMode.js
@@ -1,16 +0,0 @@
-"use strict";
-
-var gTestTab;
-var gContentAPI;
-var gContentWindow;
-
-add_task(setup_UITourTest);
-
-add_UITour_task(async function() {
-  ok(!gBrowser.selectedBrowser.currentURI.spec.startsWith("about:reader"),
-     "Should not be in reader mode at start of test.");
-  await gContentAPI.toggleReaderMode();
-  await waitForConditionPromise(() => gBrowser.selectedBrowser.currentURI.spec.startsWith("about:reader"));
-  ok(gBrowser.selectedBrowser.currentURI.spec.startsWith("about:reader"),
-     "Should be in reader mode now.");
-});
--- a/browser/components/uitour/test/browser.ini
+++ b/browser/components/uitour/test/browser.ini
@@ -34,7 +34,6 @@
 [browser_UITour_annotation_size_attributes.js]
 [browser_UITour_defaultBrowser.js]
 [browser_UITour_detach_tab.js]
-[browser_UITour_forceReaderMode.js]
 [browser_UITour_modalDialog.js]
 skip-if = os != "mac" # modal dialog disabling only working on OS X.
 [browser_UITour_observe.js]
@@ -46,4 +45,3 @@
 [browser_UITour_resetProfile.js]
 [browser_UITour_showNewTab.js]
 [browser_UITour_sync.js]
-[browser_UITour_toggleReaderMode.js]
--- a/browser/components/sessionstore/test/browser.ini
+++ b/browser/components/sessionstore/test/browser.ini
@@ -31,7 +31,6 @@
   browser_scrollPositions_sample.html
   browser_scrollPositions_sample2.html
   browser_scrollPositions_sample_frameset.html
-  browser_scrollPositions_readerModeArticle.html
   browser_sessionStorage.html
   browser_speculative_connect.html
   browser_248970_b_sample.html
@@ -111,7 +110,6 @@
 [browser_restore_redirect.js]
 [browser_restore_cookies_noOriginAttributes.js]
 [browser_scrollPositions.js]
-[browser_scrollPositionsReaderMode.js]
 [browser_sessionHistory.js]
 support-files =
   file_sessionHistory_hashchange.html
--- a/browser/base/content/urlbarBindings.xml
+++ b/browser/base/content/urlbarBindings.xml
@@ -230,11 +230,6 @@
                 break;
               }
             }
-          } else {
-            let originalUrl = ReaderMode.getOriginalUrlObjectForDisplay(aValue);
-            if (originalUrl) {
-              returnValue = originalUrl.displaySpec;
-            }
           }
 
           // Set the actiontype only if the user is not overriding actions.
@@ -947,26 +942,6 @@
         ]]></body>
       </method>
 
-      <method name="makeURIReadable">
-        <parameter name="aURI"/>
-        <body>
-          <![CDATA[
-            // Avoid copying 'about:reader?url=', and always provide the original URI:
-            // Reader mode ensures we call createExposableURI itself.
-            let readerStrippedURI = ReaderMode.getOriginalUrlObjectForDisplay(aURI.displaySpec);
-            if (readerStrippedURI) {
-              aURI = readerStrippedURI;
-            } else {
-              // Only copy exposable URIs
-              try {
-                aURI = Services.uriFixup.createExposableURI(aURI);
-              } catch (ex) {}
-            }
-            return aURI;
-          ]]>
-        </body>
-      </method>
-
       <method name="_getSelectedValueForClipboard">
         <body><![CDATA[
           // Grab the actual input field's value, not our value, which could include moz-action:
@@ -1008,8 +983,6 @@
               return selectedVal;
           }
 
-          uri = this.makeURIReadable(uri);
-
           // If the entire URL is selected, just use the actual loaded URI,
           // unless we want a decoded URI, or it's a data: or javascript: URI,
           // since those are hard to read when encoded.
--- a/browser/modules/moz.build
+++ b/browser/modules/moz.build
@@ -85,9 +85,6 @@
 with Files("ProcessHangMonitor.jsm"):
     BUG_COMPONENT = ("Core", "DOM: Content Processes")
 
-with Files("ReaderParent.jsm"):
-    BUG_COMPONENT = ("Toolkit", "Reader Mode")
-
 with Files("Sanitizer.jsm"):
     BUG_COMPONENT = ("Firefox", "Preferences")
 
@@ -149,7 +146,6 @@
     'PingCentre.jsm',
     'PluginContent.jsm',
     'ProcessHangMonitor.jsm',
-    'ReaderParent.jsm',
     'RecentWindow.jsm',
     'RemotePrompt.jsm',
     'Sanitizer.jsm',