--- a/browser/base/content/aboutNetError.xhtml
+++ b/browser/base/content/aboutNetError.xhtml
@@ -89,22 +89,16 @@
         } catch (e) {
           // We probably tried to reload a URI that caused an exception to
           // occur;  e.g. a nonexistent file.
         }
 
         buttonEl.disabled = true;
       }
 
-      function doOverride(buttonEl) {
-        var event = new CustomEvent("AboutNetErrorOverride", {bubbles:true});
-        document.dispatchEvent(event);
-        retryThis(buttonEl);
-      }
-
       function toggleDisplay(node) {
         const toggle = {
           "": "block",
           "none": "block",
           "block": "none"
         };
         return (node.style.display = toggle[node.style.display]);
       }
@@ -119,20 +113,19 @@
         panel.style.display = "block";
         document.getElementById("netErrorButtonContainer").style.display = "none";
         document.getElementById("prefResetButton").addEventListener("click", function resetPreferences(e) {
           const event = new CustomEvent("AboutNetErrorResetPreferences", {bubbles:true});
           document.dispatchEvent(event);
         });
       }
 
-      function showAdvancedButton(allowOverride) {
+      function showAdvancedButton() {
         // Get the hostname and add it to the panel
-        var panelId = gIsCertError ? "badCertAdvancedPanel" : "weakCryptoAdvancedPanel";
-        var panel = document.getElementById(panelId);
+        var panel = document.getElementById("badCertAdvancedPanel");
         for (var span of panel.querySelectorAll("span.hostname")) {
           span.textContent = document.location.hostname;
         }
         if (!gIsCertError) {
           panel.replaceChild(document.getElementById("errorLongDesc"),
                              document.getElementById("advancedLongDesc"));
         }
 
@@ -149,32 +142,26 @@
           }
 
           if (panel.style.display == "block") {
             // send event to trigger telemetry ping
             var event = new CustomEvent("AboutNetErrorUIExpanded", {bubbles:true});
             document.dispatchEvent(event);
           }
         });
-
-        if (allowOverride) {
-          document.getElementById("overrideWeakCryptoPanel").style.display = "flex";
-          var overrideLink = document.getElementById("overrideWeakCrypto");
-          overrideLink.addEventListener("click", () => doOverride(overrideLink), false);
-        }
       }
 
       function initPageCertError() {
         document.body.className = "certerror";
         document.title = document.getElementById("certErrorPageTitle").textContent;
         for (let host of document.querySelectorAll(".hostname")) {
           host.textContent = document.location.hostname;
         }
 
-        showAdvancedButton(true);
+        showAdvancedButton();
 
         var cssClass = getCSSClass();
         if (cssClass == "expertBadCert") {
           toggleDisplay(document.getElementById("badCertAdvancedPanel"));
           // Toggling the advanced panel must ensure that the debugging
           // information panel is hidden as well, since it's opened by the
           // error code link in the advanced panel.
           var div = document.getElementById("certificateErrorDebugInformation");
@@ -259,20 +246,16 @@
 
         if (err == "sslv3Used") {
           document.getElementById("learnMoreContainer").style.display = "block";
           let learnMoreLink = document.getElementById("learnMoreLink");
           learnMoreLink.href = "https://support.mozilla.org/kb/how-resolve-sslv3-error-messages-firefox";
           document.body.className = "certerror";
         }
 
-        if (err == "weakCryptoUsed") {
-          document.body.className = "certerror";
-        }
-
         // remove undisplayed errors to avoid bug 39098
         var errContainer = document.getElementById("errorContainer");
         errContainer.parentNode.removeChild(errContainer);
 
         var className = getCSSClass();
         if (className && className != "expertBadCert") {
           // Associate a CSS class with the root of the page, if one was passed in,
           // to allow custom styling.
@@ -298,27 +281,24 @@
         if (err == "cspBlocked") {
           // Remove the "Try again" button for CSP violations, since it's
           // almost certainly useless. (Bug 553180)
           document.getElementById("netErrorButtonContainer").style.display = "none";
         }
 
         window.addEventListener("AboutNetErrorOptions", function(evt) {
         // Pinning errors are of type nssFailure2
-          if (getErrorCode() == "nssFailure2" || getErrorCode() == "weakCryptoUsed") {
+          if (getErrorCode() == "nssFailure2") {
             document.getElementById("learnMoreContainer").style.display = "block";
             let learnMoreLink = document.getElementById("learnMoreLink");
             // nssFailure2 also gets us other non-overrideable errors. Choose
             // a "learn more" link based on description:
             if (getDescription().includes("mozilla_pkix_error_key_pinning_failure")) {
               learnMoreLink.href = "https://support.mozilla.org/kb/certificate-pinning-reports";
             }
-            if (getErrorCode() == "weakCryptoUsed") {
-              learnMoreLink.href = "https://support.mozilla.org/kb/how-resolve-weak-crypto-error-messages-firefox";
-            }
 
             var options = JSON.parse(evt.detail);
             if (options && options.enabled) {
               var checkbox = document.getElementById("automaticallyReportInFuture");
               showCertificateErrorReporting();
               if (options.automatic) {
                 // set the checkbox
                 checkbox.checked = true;
@@ -338,18 +318,18 @@
               "SSL_ERROR_NO_CYPHER_OVERLAP",
               "SSL_ERROR_NO_CIPHERS_SUPPORTED"
             ].some((substring) => getDescription().includes(substring));
             // If it looks like an error that is user config based
             if (getErrorCode() == "nssFailure2" && hasPrefStyleError && options && options.changedCertPrefs) {
               showPrefChangeContainer();
             }
           }
-          if (getErrorCode() == "weakCryptoUsed" || getErrorCode() == "sslv3Used") {
-            showAdvancedButton(getErrorCode() == "weakCryptoUsed");
+          if (getErrorCode() == "sslv3Used") {
+            showAdvancedButton();
           }
         }.bind(this), true, true);
 
         var event = new CustomEvent("AboutNetErrorLoad", {bubbles:true});
         document.dispatchEvent(event);
 
         if (err == "inadequateSecurityError") {
           // Remove the "Try again" button for HTTP/2 inadequate security as it
@@ -465,18 +445,17 @@
          * The certificate is only valid for garage.maemo.org
          */
         if (thisHost.endsWith("." + okHost))
           link.href = proto + okHost;
 
         // If we set a link, meaning there's something helpful for
         // the user here, expand the section by default
         if (link.href && getCSSClass() != "expertBadCert") {
-          var panelId = gIsCertError ? "badCertAdvancedPanel" : "weakCryptoAdvancedPanel"
-          toggleDisplay(document.getElementById(panelId));
+          toggleDisplay(document.getElementById("badCertAdvancedPanel"));
           if (gIsCertError) {
             // Toggling the advanced panel must ensure that the debugging
             // information panel is hidden as well, since it's opened by the
             // error code link in the advanced panel.
             var div = document.getElementById("certificateErrorDebugInformation");
             div.style.display = "none";
           }
         }
@@ -519,17 +498,16 @@
         <h1 id="et_contentEncodingError">&contentEncodingError.title;</h1>
         <h1 id="et_unsafeContentType">&unsafeContentType.title;</h1>
         <h1 id="et_nssFailure2">&nssFailure2.title;</h1>
         <h1 id="et_nssBadCert">&certerror.longpagetitle1;</h1>
         <h1 id="et_cspBlocked">&cspBlocked.title;</h1>
         <h1 id="et_remoteXUL">&remoteXUL.title;</h1>
         <h1 id="et_corruptedContentErrorv2">&corruptedContentErrorv2.title;</h1>
         <h1 id="et_sslv3Used">&sslv3Used.title;</h1>
-        <h1 id="et_weakCryptoUsed">&weakCryptoUsed.title;</h1>
         <h1 id="et_inadequateSecurityError">&inadequateSecurityError.title;</h1>
       </div>
       <div id="errorDescriptionsContainer">
         <div id="ed_generic">&generic.longDesc;</div>
         <div id="ed_dnsNotFound">&dnsNotFound.longDesc;</div>
         <div id="ed_fileNotFound">&fileNotFound.longDesc;</div>
         <div id="ed_fileAccessDenied">&fileAccessDenied.longDesc;</div>
         <div id="ed_malformedURI">&malformedURI.longDesc;</div>
@@ -548,17 +526,16 @@
         <div id="ed_contentEncodingError">&contentEncodingError.longDesc;</div>
         <div id="ed_unsafeContentType">&unsafeContentType.longDesc;</div>
         <div id="ed_nssFailure2">&nssFailure2.longDesc2;</div>
         <div id="ed_nssBadCert">&certerror.introPara;</div>
         <div id="ed_cspBlocked">&cspBlocked.longDesc;</div>
         <div id="ed_remoteXUL">&remoteXUL.longDesc;</div>
         <div id="ed_corruptedContentErrorv2">&corruptedContentErrorv2.longDesc;</div>
         <div id="ed_sslv3Used">&sslv3Used.longDesc2;</div>
-        <div id="ed_weakCryptoUsed">&weakCryptoUsed.longDesc2;</div>
         <div id="ed_inadequateSecurityError">&inadequateSecurityError.longDesc;</div>
       </div>
     </div>
 
     <!-- PAGE CONTAINER (for styling purposes only) -->
     <div id="errorPageContainer" class="container">
 
       <!-- Error Title -->
@@ -622,26 +599,16 @@
       <div id="certificateErrorReporting">
         <p class="toggle-container-with-text">
           <input type="checkbox" id="automaticallyReportInFuture" />
           <label for="automaticallyReportInFuture" id="automaticallyReportInFuture">&errorReporting.automatic2;</label>
         </p>
       </div>
 
       <div id="advancedPanelContainer">
-        <div id="weakCryptoAdvancedPanel" class="advanced-panel">
-          <div id="weakCryptoAdvancedDescription">
-            <p>&weakCryptoAdvanced.longDesc;</p>
-          </div>
-          <div id="advancedLongDesc" />
-          <div id="overrideWeakCryptoPanel">
-            <a id="overrideWeakCrypto" href="#">&weakCryptoAdvanced.override;</a>
-          </div>
-        </div>
-
         <div id="badCertAdvancedPanel" class="advanced-panel">
           <p id="badCertTechnicalInfo"/>
           <button id="exceptionDialogButton">&securityOverride.exceptionButtonLabel;</button>
         </div>
       </div>
 
     </div>
 

--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -2743,30 +2743,28 @@ var BrowserOnClick = {
     let mm = window.messageManager;
     mm.addMessageListener("Browser:CertExceptionError", this);
     mm.addMessageListener("Browser:SiteBlockedError", this);
     mm.addMessageListener("Browser:EnableOnlineMode", this);
     mm.addMessageListener("Browser:SendSSLErrorReport", this);
     mm.addMessageListener("Browser:SetSSLErrorReportAuto", this);
     mm.addMessageListener("Browser:ResetSSLPreferences", this);
     mm.addMessageListener("Browser:SSLErrorReportTelemetry", this);
-    mm.addMessageListener("Browser:OverrideWeakCrypto", this);
     mm.addMessageListener("Browser:SSLErrorGoBack", this);
   },
 
   uninit: function() {
     let mm = window.messageManager;
     mm.removeMessageListener("Browser:CertExceptionError", this);
     mm.removeMessageListener("Browser:SiteBlockedError", this);
     mm.removeMessageListener("Browser:EnableOnlineMode", this);
     mm.removeMessageListener("Browser:SendSSLErrorReport", this);
     mm.removeMessageListener("Browser:SetSSLErrorReportAuto", this);
     mm.removeMessageListener("Browser:ResetSSLPreferences", this);
     mm.removeMessageListener("Browser:SSLErrorReportTelemetry", this);
-    mm.removeMessageListener("Browser:OverrideWeakCrypto", this);
     mm.removeMessageListener("Browser:SSLErrorGoBack", this);
   },
 
   handleEvent: function(event) {
     if (!event.isTrusted || // Don't trust synthetic events
         event.button == 2) {
       return;
     }
@@ -2820,23 +2818,16 @@ var BrowserOnClick = {
         }
         Services.telemetry.getHistogramById("TLS_ERROR_REPORT_UI").add(bin);
       break;
       case "Browser:SSLErrorReportTelemetry":
         let reportStatus = msg.data.reportStatus;
         Services.telemetry.getHistogramById("TLS_ERROR_REPORT_UI")
           .add(reportStatus);
       break;
-      case "Browser:OverrideWeakCrypto":
-        let weakCryptoOverride = Cc["@mozilla.org/security/weakcryptooverride;1"]
-                                   .getService(Ci.nsIWeakCryptoOverride);
-        weakCryptoOverride.addWeakCryptoOverride(
-          msg.data.uri.host,
-          PrivateBrowsingUtils.isBrowserPrivate(gBrowser.selectedBrowser));
-      break;
       case "Browser:SSLErrorGoBack":
         goBackFromErrorPage();
       break;
     }
   },
 
   onSSLErrorReport: function(browser, uri, securityInfo) {
     if (!Services.prefs.getBoolPref("security.ssl.errorReporting.enabled")) {
@@ -6825,17 +6816,16 @@ var gIdentityHandler = {
 
     // Then, update the user interface with the available data.
     this.refreshIdentityBlock();
     // Handle a location change while the Control Center is focused
     // by closing the popup (bug 1207542)
     if (shouldHidePopup) {
       this._identityPopup.hidePopup();
     }
-    this.showWeakCryptoInfoBar();
 
     // NOTE: We do NOT update the identity popup (the control center) when
     // we receive a new security state on the existing page (i.e. from a
     // subframe). If the user opened the popup and looks at the provided
     // information we don't want to suddenly change the panel contents.
   },
 
   /**
@@ -7015,65 +7005,16 @@ var gIdentityHandler = {
     // Set cropping and direction
     this._identityIconLabel.crop = icon_country_label ? "end" : "center";
     this._identityIconLabel.parentNode.style.direction = icon_labels_dir;
     // Hide completely if the organization label is empty
     this._identityIconLabel.parentNode.collapsed = icon_label ? false : true;
   },
 
   /**
-   * Show the weak crypto notification bar.
-   */
-  showWeakCryptoInfoBar() {
-    if (!this._uriHasHost || !this._isBroken || !this._sslStatus.cipherName ||
-        this._sslStatus.cipherName.indexOf("_RC4_") < 0) {
-      return;
-    }
-
-    let notificationBox = gBrowser.getNotificationBox();
-    let notification = notificationBox.getNotificationWithValue("weak-crypto");
-    if (notification) {
-      return;
-    }
-
-    let brandBundle = document.getElementById("bundle_brand");
-    let brandShortName = brandBundle.getString("brandShortName");
-    let message = gNavigatorBundle.getFormattedString("weakCryptoOverriding.message",
-                                                      [brandShortName]);
-
-    let host = this._uri.host;
-    let port = 443;
-    try {
-      if (this._uri.port > 0) {
-        port = this._uri.port;
-      }
-    } catch (e) {}
-
-    let buttons = [{
-      label: gNavigatorBundle.getString("revokeOverride.label"),
-      accessKey: gNavigatorBundle.getString("revokeOverride.accesskey"),
-      callback: function(aNotification, aButton) {
-        try {
-          let weakCryptoOverride = Cc["@mozilla.org/security/weakcryptooverride;1"]
-                                     .getService(Ci.nsIWeakCryptoOverride);
-          weakCryptoOverride.removeWeakCryptoOverride(host, port,
-            PrivateBrowsingUtils.isBrowserPrivate(gBrowser.selectedBrowser));
-          BrowserReloadWithFlags(nsIWebNavigation.LOAD_FLAGS_BYPASS_CACHE);
-        } catch (e) {
-          Cu.reportError(e);
-        }
-      }
-    }];
-
-    const priority = notificationBox.PRIORITY_WARNING_MEDIUM;
-    notificationBox.appendNotification(message, "weak-crypto", null,
-                                       priority, buttons);
-  },
-
-  /**
    * Set up the title and content messages for the identity message popup,
    * based on the specified mode, and the details of the SSL cert, where
    * applicable
    */
   refreshIdentityPopup() {
     // Update "Learn More" for Mixed Content Blocking and Insecure Login Forms.
     let baseURL = Services.urlFormatter.formatURLPref("app.support.baseURL");
     this._identityPopupMixedContentLearnMore

--- a/browser/base/content/content.js
+++ b/browser/base/content/content.js
@@ -346,19 +346,16 @@ var AboutNetAndCertErrorListener = {
 
     switch (aEvent.type) {
     case "AboutNetErrorLoad":
       this.onPageLoad(aEvent);
       break;
     case "AboutNetErrorSetAutomatic":
       this.onSetAutomatic(aEvent);
       break;
-    case "AboutNetErrorOverride":
-      this.onOverride(aEvent);
-      break;
     case "AboutNetErrorResetPreferences":
       this.onResetPreferences(aEvent);
       break;
     }
   },
 
   changedCertPrefs: function() {
     for (let prefName of PREF_SSL_IMPACT) {
@@ -405,21 +402,16 @@ var AboutNetAndCertErrorListener = {
       let {host, port} = content.document.mozDocumentURIIfNotForErrorPages;
       sendAsyncMessage("Browser:SendSSLErrorReport", {
         uri: { host, port },
         securityInfo: getSerializedSecurityInfo(docShell),
       });
 
     }
   },
-
-  onOverride: function(evt) {
-    let {host, port} = content.document.mozDocumentURIIfNotForErrorPages;
-    sendAsyncMessage("Browser:OverrideWeakCrypto", { uri: {host, port} });
-  }
 }
 
 AboutNetAndCertErrorListener.init(this);
 
 
 var ClickEventHandler = {
   init: function init() {
     Cc["@mozilla.org/eventlistenerservice;1"]

--- a/browser/base/content/test/general/browser_misused_characters_in_strings.js
+++ b/browser/base/content/test/general/browser_misused_characters_in_strings.js
@@ -13,24 +13,16 @@ let gWhitelist = [{
     key: "searchForSomethingWith",
     type: "single-quote"
   }, {
     file: "netError.dtd",
     key: "certerror.introPara",
     type: "single-quote"
   }, {
     file: "netError.dtd",
-    key: "weakCryptoAdvanced.longDesc",
-    type: "single-quote"
-  }, {
-    file: "netError.dtd",
-    key: "weakCryptoAdvanced.override",
-    type: "single-quote"
-  }, {
-    file: "netError.dtd",
     key: "inadequateSecurityError.longDesc",
     type: "single-quote"
   }, {
     file: "netError.dtd",
     key: "certerror.wrongSystemTime",
     type: "single-quote"
   }, {
     file: "phishing-afterload-warning-message.dtd",

--- a/browser/locales/en-US/chrome/browser/browser.properties
+++ b/browser/locales/en-US/chrome/browser/browser.properties
@@ -696,21 +696,16 @@ userContext.aboutPage.accesskey = O
 
 userContextOpenLink.label = Open Link in New %S Tab
 
 muteTab.label = Mute Tab
 muteTab.accesskey = M
 unmuteTab.label = Unmute Tab
 unmuteTab.accesskey = M
 
-# LOCALIZATION NOTE (weakCryptoOverriding.message): %S is brandShortName
-weakCryptoOverriding.message = %S recommends that you don’t enter your password, credit card and other personal information on this website.
-revokeOverride.label = Don’t Trust This Website
-revokeOverride.accesskey = D
-
 # LOCALIZATION NOTE (certErrorDetails*.label): These are text strings that
 # appear in the about:certerror page, so that the user can copy and send them to
 # the server administrators for troubleshooting.
 certErrorDetailsHSTS.label = HTTP Strict Transport Security: %S
 certErrorDetailsKeyPinning.label = HTTP Public Key Pinning: %S
 certErrorDetailsCertChain.label = Certificate chain:
 
 # LOCALIZATION NOTE (pendingCrashReports2.label): Semi-colon list of plural forms

--- a/browser/locales/en-US/chrome/overrides/appstrings.properties
+++ b/browser/locales/en-US/chrome/overrides/appstrings.properties
@@ -33,11 +33,9 @@ externalProtocolLaunchBtn=Launch applica
 malwareBlocked=The site at %S has been reported as an attack site and has been blocked based on your security preferences.
 unwantedBlocked=The site at %S has been reported as serving unwanted software and has been blocked based on your security preferences.
 deceptiveBlocked=This web page at %S has been reported as a deceptive site and has been blocked based on your security preferences.
 cspBlocked=This page has a content security policy that prevents it from being loaded in this way.
 corruptedContentErrorv2=The site at %S has experienced a network protocol violation that cannot be repaired.
 remoteXUL=This page uses an unsupported technology that is no longer available by default in Firefox.
 ## LOCALIZATION NOTE (sslv3Used) - Do not translate "%S".
 sslv3Used=Firefox cannot guarantee the safety of your data on %S because it uses SSLv3, a broken security protocol.
-## LOCALIZATION NOTE (weakCryptoUsed) - Do not translate "%S".
-weakCryptoUsed=The owner of %S has configured their website improperly. To protect your information from being stolen, Firefox has not connected to this website.
 inadequateSecurityError=The website tried to negotiate an inadequate level of security.

--- a/browser/locales/en-US/chrome/overrides/netError.dtd
+++ b/browser/locales/en-US/chrome/overrides/netError.dtd
@@ -184,24 +184,16 @@ was trying to connect. -->
 <!ENTITY remoteXUL.title "Remote XUL">
 <!ENTITY remoteXUL.longDesc "<p><ul><li>Please contact the website owners to inform them of this problem.</li></ul></p>">
 
 <!ENTITY sslv3Used.title "Unable to Connect Securely">
 <!-- LOCALIZATION NOTE (sslv3Used.longDesc2) - Do not translate
      "SSL_ERROR_UNSUPPORTED_VERSION". -->
 <!ENTITY sslv3Used.longDesc2 "Advanced info: SSL_ERROR_UNSUPPORTED_VERSION">
 
-<!ENTITY weakCryptoUsed.title "Your connection is not secure">
-<!-- LOCALIZATION NOTE (weakCryptoUsed.longDesc2) - Do not translate
-     "SSL_ERROR_NO_CYPHER_OVERLAP". -->
-<!ENTITY weakCryptoUsed.longDesc2 "Advanced info: SSL_ERROR_NO_CYPHER_OVERLAP">
-<!ENTITY weakCryptoAdvanced.title "Advanced">
-<!ENTITY weakCryptoAdvanced.longDesc "<span class='hostname'></span> uses security technology that is outdated and vulnerable to attack. An attacker could easily reveal information which you thought to be safe.">
-<!ENTITY weakCryptoAdvanced.override "(Not secure) Try loading <span class='hostname'></span> using outdated security">
-
 <!-- LOCALIZATION NOTE (certerror.wrongSystemTime) - The <span id='..' /> tags will be injected with actual values,
      please leave them unchanged. -->
 <!ENTITY certerror.wrongSystemTime "<p>A secure connection to <span id='wrongSystemTime_URL'/> isn’t possible because your clock appears to show the wrong time.</p> <p>Your computer thinks it is <span id='wrongSystemTime_systemDate'/>, when it should be <span id='wrongSystemTime_actualDate'/>. To fix this problem, change your date and time settings to match the correct time.</p>">
 
 <!ENTITY certerror.pagetitle1  "Insecure Connection">
 <!ENTITY certerror.whatShouldIDo.badStsCertExplanation "This site uses HTTP
 Strict Transport Security (HSTS) to specify that &brandShortName; may only connect
 to it securely. As a result, it is not possible to add an exception for this