--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -7323,38 +7323,23 @@ var gIdentityHandler = {
    * "identity-popup" panel.
    */
   handleMoreInfoClick(event) {
     displaySecurityInfo();
     event.stopPropagation();
     this._identityPopup.hidePopup();
   },
 
-  toggleSubView(name, anchor) {
-    let view = this._identityPopupMultiView;
-    let id = `identity-popup-${name}View`;
-    let subView = document.getElementById(id);
-
-    // Listen for the subview showing or hiding to change
-    // the tooltip on the expander button.
-    subView.addEventListener("ViewShowing", this);
-    subView.addEventListener("ViewHiding", this);
-
-    if (view.showingSubView) {
-      view.showMainView();
-    } else {
-      view.showSubView(id, anchor);
-    }
-
-    // If an element is focused that's not the anchor, clear the focus.
+  showSecuritySubView() {
+    this._identityPopupMultiView.showSubView("identity-popup-securityView",
+                                             this._popupExpander);
+
     // Elements of hidden views have -moz-user-focus:ignore but setting that
     // per CSS selector doesn't blur a focused element in those hidden views.
-    if (Services.focus.focusedElement != anchor) {
-      Services.focus.clearFocus(window);
-    }
+    Services.focus.clearFocus(window);
   },
 
   disableMixedContentProtection() {
     // Use telemetry to measure how often unblocking happens
     const kMIXED_CONTENT_UNBLOCK_EVENT = 2;
     let histogram =
       Services.telemetry.getHistogramById(
         "MIXED_CONTENT_UNBLOCK_COUNTER");
@@ -7677,17 +7662,17 @@ var gIdentityHandler = {
   refreshIdentityPopup() {
     // Update "Learn More" for Mixed Content Blocking and Insecure Login Forms.
     let baseURL = Services.urlFormatter.formatURLPref("app.support.baseURL");
     this._identityPopupMixedContentLearnMore
         .setAttribute("href", baseURL + "mixed-content");
     this._identityPopupInsecureLoginFormsLearnMore
         .setAttribute("href", baseURL + "insecure-password");
 
-    // The expander switches its tooltip when toggled, change it to the default.
+    // This is in the properties file because the expander used to switch its tooltip.
     this._popupExpander.tooltipText = gNavigatorBundle.getString("identity.showDetails.tooltip");
 
     // Determine connection security information.
     let connection = "not-secure";
     if (this._isSecureInternalUI) {
       connection = "chrome";
     } else if (this._isExtensionPage) {
       connection = "extension";
@@ -7907,26 +7892,16 @@ var gIdentityHandler = {
   onPopupHidden(event) {
     if (event.target == this._identityPopup) {
       window.removeEventListener("focus", this, true);
       this._identityBox.removeAttribute("open");
     }
   },
 
   handleEvent(event) {
-    // If the subview is shown or hidden, change the tooltip on the expander button.
-    if (event.type == "ViewShowing") {
-      this._popupExpander.tooltipText = gNavigatorBundle.getString("identity.hideDetails.tooltip");
-      return;
-    }
-    if (event.type == "ViewHiding") {
-      this._popupExpander.tooltipText = gNavigatorBundle.getString("identity.showDetails.tooltip");
-      return;
-    }
-
     let elem = document.activeElement;
     let position = elem.compareDocumentPosition(this._identityPopup);
 
     if (!(position & (Node.DOCUMENT_POSITION_CONTAINS |
                       Node.DOCUMENT_POSITION_CONTAINED_BY)) &&
         !this._identityPopup.hasAttribute("noautohide")) {
       // Hide the panel when focusing an element that is
       // neither an ancestor nor descendant unless the panel has

--- a/browser/base/content/test/general/browser_addCertException.js
+++ b/browser/base/content/test/general/browser_addCertException.js
@@ -7,44 +7,44 @@
 // Test adding a certificate exception by attempting to browse to a site with
 // a bad certificate, being redirected to the internal about:certerror page,
 // using the button contained therein to load the certificate exception
 // dialog, using that to add an exception, and finally successfully visiting
 // the site, including showing the right identity box and control center icons.
 add_task(async function() {
   await BrowserTestUtils.openNewForegroundTab(gBrowser);
   await loadBadCertPage("https://expired.example.com");
-  checkControlPanelIcons();
-  let certOverrideService = Cc["@mozilla.org/security/certoverride;1"]
-                              .getService(Ci.nsICertOverrideService);
-  certOverrideService.clearValidityOverride("expired.example.com", -1);
-  await BrowserTestUtils.removeTab(gBrowser.selectedTab);
-});
 
-// Check for the correct icons in the identity box and control center.
-function checkControlPanelIcons() {
   let { gIdentityHandler } = gBrowser.ownerGlobal;
   gIdentityHandler._identityBox.click();
+  let promiseViewShown = BrowserTestUtils.waitForEvent(gIdentityHandler._identityPopup, "ViewShown");
   document.getElementById("identity-popup-security-expander").click();
+  await promiseViewShown;
 
   is_element_visible(document.getElementById("connection-icon"), "Should see connection icon");
   let connectionIconImage = gBrowser.ownerGlobal
         .getComputedStyle(document.getElementById("connection-icon"))
         .getPropertyValue("list-style-image");
   let securityViewBG = gBrowser.ownerGlobal
-        .getComputedStyle(document.getElementById("identity-popup-securityView"))
+        .getComputedStyle(document.getElementById("identity-popup-securityView")
+                                  .getElementsByClassName("identity-popup-security-content")[0])
         .getPropertyValue("background-image");
   let securityContentBG = gBrowser.ownerGlobal
-        .getComputedStyle(document.getElementById("identity-popup-security-content"))
+        .getComputedStyle(document.getElementById("identity-popup-mainView")
+                                  .getElementsByClassName("identity-popup-security-content")[0])
         .getPropertyValue("background-image");
   is(connectionIconImage,
      "url(\"chrome://browser/skin/connection-mixed-passive-loaded.svg\")",
      "Using expected icon image in the identity block");
   is(securityViewBG,
      "url(\"chrome://browser/skin/connection-mixed-passive-loaded.svg\")",
      "Using expected icon image in the Control Center main view");
   is(securityContentBG,
      "url(\"chrome://browser/skin/connection-mixed-passive-loaded.svg\")",
      "Using expected icon image in the Control Center subview");
 
   gIdentityHandler._identityPopup.hidden = true;
-}
 
+  let certOverrideService = Cc["@mozilla.org/security/certoverride;1"]
+                              .getService(Ci.nsICertOverrideService);
+  certOverrideService.clearValidityOverride("expired.example.com", -1);
+  await BrowserTestUtils.removeTab(gBrowser.selectedTab);
+});

--- a/browser/base/content/test/siteIdentity/browser_identity_UI.js
+++ b/browser/base/content/test/siteIdentity/browser_identity_UI.js
@@ -98,21 +98,23 @@ function nextTest() {
     if (spec == "about:blank" || spec == gCurrentTest.location) {
       BrowserTestUtils.loadURI(gBrowser.selectedBrowser, gCurrentTest.location);
     } else {
       // Open the Control Center and make sure it closes after nav (Bug 1207542).
       let popupShown = BrowserTestUtils.waitForEvent(gIdentityHandler._identityPopup, "popupshown");
       gPopupHidden = BrowserTestUtils.waitForEvent(gIdentityHandler._identityPopup, "popuphidden");
       gIdentityHandler._identityBox.click();
       info("Waiting for the Control Center to be shown");
-      popupShown.then(() => {
+      popupShown.then(async () => {
         ok(!is_hidden(gIdentityHandler._identityPopup), "Control Center is visible");
         // Show the subview, which is an easy way in automation to reproduce
         // Bug 1207542, where the CC wouldn't close on navigation.
+        let promiseViewShown = BrowserTestUtils.waitForEvent(gIdentityHandler._identityPopup, "ViewShown");
         gBrowser.ownerDocument.querySelector("#identity-popup-security-expander").click();
+        await promiseViewShown;
         BrowserTestUtils.loadURI(gBrowser.selectedBrowser, gCurrentTest.location);
       });
     }
   } else {
     gCheckETLD = false;
     gTestDesc = "#" + gCurrentTestIndex + " (" + gCurrentTest.name + " without eTLD in identity icon label)";
     if (!gForward)
       gTestDesc += " (second time)";

--- a/browser/base/content/test/siteIdentity/browser_insecureLoginForms.js
+++ b/browser/base/content/test/siteIdentity/browser_insecureLoginForms.js
@@ -33,51 +33,64 @@ add_task(async function test_simple() {
       BrowserTestUtils.switchTab(gBrowser, tab),
       BrowserTestUtils.browserLoaded(browser),
       // One event is triggered by pageshow and one by DOMFormHasPassword.
       waitForInsecureLoginFormsStateChange(browser, 2),
     ]);
 
     let { gIdentityHandler } = gBrowser.ownerGlobal;
     gIdentityHandler._identityBox.click();
+
+    // Messages should be visible when the scheme is HTTP, and invisible when
+    // the scheme is HTTPS.
+    is(Array.every(document.getElementById("identity-popup-mainView")
+                           .querySelectorAll("[when-loginforms=insecure]"),
+                   element => !is_hidden(element)),
+       expectWarning,
+       "The relevant messages should be visible or hidden in the main view.");
+
     let promiseViewShown = BrowserTestUtils.waitForEvent(gIdentityHandler._identityPopup, "ViewShown");
     document.getElementById("identity-popup-security-expander").click();
     await promiseViewShown;
 
     if (expectWarning) {
       ok(is_visible(document.getElementById("connection-icon")), "Connection icon should be visible");
       let connectionIconImage = gBrowser.ownerGlobal
             .getComputedStyle(document.getElementById("connection-icon"))
             .getPropertyValue("list-style-image");
       let securityViewBG = gBrowser.ownerGlobal
-            .getComputedStyle(document.getElementById("identity-popup-securityView"))
+            .getComputedStyle(document.getElementById("identity-popup-securityView")
+                                      .getElementsByClassName("identity-popup-security-content")[0])
             .getPropertyValue("background-image");
       let securityContentBG = gBrowser.ownerGlobal
-            .getComputedStyle(document.getElementById("identity-popup-security-content"))
+            .getComputedStyle(document.getElementById("identity-popup-mainView")
+                                      .getElementsByClassName("identity-popup-security-content")[0])
             .getPropertyValue("background-image");
       is(connectionIconImage,
          "url(\"chrome://browser/skin/connection-mixed-active-loaded.svg\")",
          "Using expected icon image in the identity block");
       is(securityViewBG,
          "url(\"chrome://browser/skin/controlcenter/mcb-disabled.svg\")",
          "Using expected icon image in the Control Center main view");
       is(securityContentBG,
          "url(\"chrome://browser/skin/controlcenter/mcb-disabled.svg\")",
          "Using expected icon image in the Control Center subview");
-      is(Array.filter(document.querySelectorAll("[observes=identity-popup-insecure-login-forms-learn-more]"),
+      is(Array.filter(document.getElementById("identity-popup-securityView")
+                              .querySelectorAll("[observes=identity-popup-insecure-login-forms-learn-more]"),
                       element => !is_hidden(element)).length, 1,
          "The 'Learn more' link should be visible once.");
     }
 
     // Messages should be visible when the scheme is HTTP, and invisible when
     // the scheme is HTTPS.
-    is(Array.every(document.querySelectorAll("[when-loginforms=insecure]"),
+    is(Array.every(document.getElementById("identity-popup-securityView")
+                           .querySelectorAll("[when-loginforms=insecure]"),
                    element => !is_hidden(element)),
        expectWarning,
-       "The relevant messages should be visible or hidden.");
+       "The relevant messages should be visible or hidden in the security view.");
 
     if (gIdentityHandler._identityPopup.state != "closed") {
       let hideEvent = BrowserTestUtils.waitForEvent(gIdentityHandler._identityPopup, "popuphidden");
       info("hiding popup");
       gIdentityHandler._identityPopup.hidePopup();
       await hideEvent;
     }
 
@@ -129,46 +142,55 @@ add_task(async function test_ignoring_wi
     });
     let tab = await loaded;
     browser = tab.linkedBrowser;
     await waitForInsecureLoginFormsStateChange(browser, 2);
 
     // Open the identity popup.
     let { gIdentityHandler } = gBrowser.ownerGlobal;
     gIdentityHandler._identityBox.click();
+
+    ok(Array.every(document.getElementById("identity-popup-mainView")
+                           .querySelectorAll("[when-loginforms=insecure]"),
+                   element => is_hidden(element)),
+       "All messages should be hidden in the main view.");
+
     let promiseViewShown = BrowserTestUtils.waitForEvent(gIdentityHandler._identityPopup, "ViewShown");
     document.getElementById("identity-popup-security-expander").click();
     await promiseViewShown;
 
     ok(is_visible(document.getElementById("connection-icon")),
        "Connection icon is visible");
 
     // Assert that the identity indicators are still "secure".
     let connectionIconImage = gBrowser.ownerGlobal
           .getComputedStyle(document.getElementById("connection-icon"))
           .getPropertyValue("list-style-image");
     let securityViewBG = gBrowser.ownerGlobal
-          .getComputedStyle(document.getElementById("identity-popup-securityView"))
+          .getComputedStyle(document.getElementById("identity-popup-securityView")
+                                    .getElementsByClassName("identity-popup-security-content")[0])
           .getPropertyValue("background-image");
     let securityContentBG = gBrowser.ownerGlobal
-          .getComputedStyle(document.getElementById("identity-popup-security-content"))
+          .getComputedStyle(document.getElementById("identity-popup-mainView")
+                                    .getElementsByClassName("identity-popup-security-content")[0])
           .getPropertyValue("background-image");
     is(connectionIconImage,
        "url(\"chrome://browser/skin/connection-secure.svg\")",
        "Using expected icon image in the identity block");
     is(securityViewBG,
        "url(\"chrome://browser/skin/controlcenter/connection.svg\")",
        "Using expected icon image in the Control Center main view");
     is(securityContentBG,
        "url(\"chrome://browser/skin/controlcenter/connection.svg\")",
        "Using expected icon image in the Control Center subview");
 
-    ok(Array.every(document.querySelectorAll("[when-loginforms=insecure]"),
+    ok(Array.every(document.getElementById("identity-popup-securityView")
+                           .querySelectorAll("[when-loginforms=insecure]"),
                    element => is_hidden(element)),
-       "All messages should be hidden.");
+       "All messages should be hidden in the security view.");
 
     if (gIdentityHandler._identityPopup.state != "closed") {
       info("hiding popup");
       let hideEvent = BrowserTestUtils.waitForEvent(gIdentityHandler._identityPopup, "popuphidden");
       gIdentityHandler._identityPopup.hidePopup();
       await hideEvent;
     }
 

--- a/browser/base/content/test/siteIdentity/head.js
+++ b/browser/base/content/test/siteIdentity/head.js
@@ -213,21 +213,24 @@ async function assertMixedContentBlockin
 
   is(popupAttr.includes("passive-loaded"), passiveLoaded,
       "identity-popup has expected attr for passiveLoaded");
   is(bodyAttr.includes("passive-loaded"), passiveLoaded,
       "securityView-body has expected attr for passiveLoaded");
 
   // Make sure the correct icon is visible in the Control Center.
   // This logic is controlled with CSS, so this helps prevent regressions there.
-  let securityView = doc.getElementById("identity-popup-securityView");
-  let securityViewBG = tabbrowser.ownerGlobal.getComputedStyle(securityView).
-                       getPropertyValue("background-image");
-  let securityContentBG = tabbrowser.ownerGlobal.getComputedStyle(securityView).
-                          getPropertyValue("background-image");
+  let securityViewBG = tabbrowser.ownerGlobal
+    .getComputedStyle(document.getElementById("identity-popup-securityView")
+                              .getElementsByClassName("identity-popup-security-content")[0])
+    .getPropertyValue("background-image");
+  let securityContentBG = tabbrowser.ownerGlobal
+    .getComputedStyle(document.getElementById("identity-popup-mainView")
+                              .getElementsByClassName("identity-popup-security-content")[0])
+    .getPropertyValue("background-image");
 
   if (stateInsecure) {
     is(securityViewBG, "url(\"chrome://browser/skin/controlcenter/conn-not-secure.svg\")",
       "CC using 'not secure' icon");
     is(securityContentBG, "url(\"chrome://browser/skin/controlcenter/conn-not-secure.svg\")",
       "CC using 'not secure' icon");
   }
 
@@ -257,17 +260,18 @@ async function assertMixedContentBlockin
         "CC using degraded icon");
     }
   }
 
   if (activeLoaded || activeBlocked || passiveLoaded) {
     let promiseViewShown = BrowserTestUtils.waitForEvent(gIdentityHandler._identityPopup, "ViewShown");
     doc.getElementById("identity-popup-security-expander").click();
     await promiseViewShown;
-    is(Array.filter(doc.querySelectorAll("[observes=identity-popup-mcb-learn-more]"),
+    is(Array.filter(doc.getElementById("identity-popup-securityView")
+                       .querySelectorAll("[observes=identity-popup-mcb-learn-more]"),
                     element => !is_hidden(element)).length, 1,
        "The 'Learn more' link should be visible once.");
   }
 
   if (gIdentityHandler._identityPopup.state != "closed") {
     let hideEvent = BrowserTestUtils.waitForEvent(gIdentityHandler._identityPopup, "popuphidden");
     info("Hiding identity popup");
     gIdentityHandler._identityPopup.hidePopup();

--- a/browser/components/controlcenter/content/panel.inc.xul
+++ b/browser/components/controlcenter/content/panel.inc.xul
@@ -1,32 +1,33 @@
 <!-- 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/. -->
 
 <panel id="identity-popup"
        type="arrow"
        hidden="true"
+       photon="true"
        role="alertdialog"
        onpopupshown="gIdentityHandler.onPopupShown(event);"
        onpopuphidden="gIdentityHandler.onPopupHidden(event);"
        orient="vertical">
 
   <broadcasterset>
     <broadcaster id="identity-popup-mcb-learn-more" class="text-link plain" value="&identity.learnMore;"/>
     <broadcaster id="identity-popup-insecure-login-forms-learn-more" class="text-link plain" value="&identity.learnMore;"/>
   </broadcasterset>
 
-  <panelmultiview id="identity-popup-multiView"
-                  mainViewId="identity-popup-mainView">
-    <panelview id="identity-popup-mainView" flex="1"
+  <photonpanelmultiview id="identity-popup-multiView"
+                        mainViewId="identity-popup-mainView">
+    <panelview id="identity-popup-mainView"
                descriptionheightworkaround="true">
       <!-- Security Section -->
       <hbox id="identity-popup-security" class="identity-popup-section">
-        <vbox id="identity-popup-security-content" flex="1">
+        <vbox class="identity-popup-security-content" flex="1">
           <label class="plain">
             <label class="identity-popup-headline identity-popup-host"></label>
             <label class="identity-popup-headline identity-popup-hostless" crop="end"/>
           </label>
           <description class="identity-popup-connection-not-secure"
                        when-connection="not-secure secure-cert-user-overridden">&identity.connectionNotSecure;</description>
           <description class="identity-popup-connection-secure"
                        when-connection="secure secure-ev">&identity.connectionSecure;</description>
@@ -43,17 +44,17 @@
             <description class="identity-popup-warning-yellow"
                          when-ciphers="weak">&identity.weakEncryption;</description>
             <description when-loginforms="insecure">&identity.insecureLoginForms2;</description>
           </vbox>
         </vbox>
         <button id="identity-popup-security-expander"
                 class="identity-popup-expander"
                 when-connection="not-secure secure secure-ev secure-cert-user-overridden"
-                oncommand="gIdentityHandler.toggleSubView('security', this)"/>
+                oncommand="gIdentityHandler.showSecuritySubView();"/>
       </hbox>
 
       <!-- Tracking Protection Section -->
       <hbox id="tracking-protection-container"
             class="identity-popup-section"
             when-connection="not-secure secure secure-ev secure-cert-user-overridden file">
         <vbox id="tracking-protection-content" flex="1">
           <label class="identity-popup-headline"
@@ -93,18 +94,19 @@
           <description id="identity-popup-permission-reload-hint">&identity.permissionsReloadHint;</description>
           <description id="identity-popup-permission-empty-hint">&identity.permissionsEmpty;</description>
         </vbox>
       </hbox>
     </panelview>
 
     <!-- Security SubView -->
     <panelview id="identity-popup-securityView"
+               title="&identity.securityView.label;"
                descriptionheightworkaround="true">
-      <vbox id="identity-popup-securityView-header">
+      <vbox class="identity-popup-security-content">
         <label class="plain">
           <label class="identity-popup-headline identity-popup-host"></label>
           <label class="identity-popup-headline identity-popup-hostless" crop="end"/>
         </label>
         <description class="identity-popup-connection-not-secure"
                      when-connection="not-secure secure-cert-user-overridden">&identity.connectionNotSecure;</description>
         <description class="identity-popup-connection-secure"
                      when-connection="secure secure-ev">&identity.connectionSecure;</description>
@@ -177,10 +179,10 @@
 
       <vbox id="identity-popup-securityView-footer">
         <!-- More Security Information -->
         <button label="&identity.moreInfoLinkText2;"
                 oncommand="gIdentityHandler.handleMoreInfoClick(event);"/>
       </vbox>
 
     </panelview>
-  </panelmultiview>
+  </photonpanelmultiview>
 </panel>

--- a/browser/components/customizableui/content/panelUI.xml
+++ b/browser/components/customizableui/content/panelUI.xml
@@ -67,17 +67,17 @@
   <binding id="panelview">
     <content>
       <xul:box class="panel-header" anonid="header">
         <xul:toolbarbutton anonid="back"
                            class="subviewbutton subviewbutton-iconic subviewbutton-back"
                            closemenu="none"
                            tabindex="0"
                            tooltip="&backCmd.label;"
-                           onclick="document.getBindingParent(this).panelMultiView.goBack(); this.blur()"/>
+                           oncommand="document.getBindingParent(this).panelMultiView.goBack(); this.blur()"/>
         <xul:label xbl:inherits="value=title"/>
       </xul:box>
       <children/>
     </content>
     <implementation>
       <property name="header"
                 readonly="true"
                 onget="return document.getAnonymousElementByAttribute(this, 'anonid', 'header');"/>

--- a/browser/locales/en-US/chrome/browser/browser.dtd
+++ b/browser/locales/en-US/chrome/browser/browser.dtd
@@ -727,16 +727,20 @@ you can use these alternative items. Oth
 <!ENTITY findSelectionCmd.commandkey "e">
 
 <!ENTITY spellAddDictionaries.label "Add Dictionaries…">
 <!ENTITY spellAddDictionaries.accesskey "A">
 
 <!ENTITY editBookmark.done.label                     "Done">
 <!ENTITY editBookmark.removeBookmark.accessKey       "R">
 
+<!-- LOCALIZATION NOTE (identity.securityView.label)
+     This is the header of the security subview in the Site Identity panel. -->
+<!ENTITY identity.securityView.label "Site Security">
+
 <!ENTITY identity.connectionSecure "Secure Connection">
 <!ENTITY identity.connectionNotSecure "Connection is Not Secure">
 <!ENTITY identity.connectionFile "This page is stored on your computer.">
 <!ENTITY identity.connectionVerified2 "You are securely connected to this site, owned by:">
 <!ENTITY identity.connectionInternal "This is a secure &brandShortName; page.">
 <!ENTITY identity.extensionPage "This page is loaded from an extension.">
 <!ENTITY identity.insecureLoginForms2 "Logins entered on this page could be compromised.">
 

--- a/browser/locales/en-US/chrome/browser/browser.properties
+++ b/browser/locales/en-US/chrome/browser/browser.properties
@@ -492,17 +492,16 @@ canvas.remember=Always remember my decis
 identity.identified.verifier=Verified by: %S
 identity.identified.verified_by_you=You have added a security exception for this site.
 identity.identified.state_and_country=%S, %S
 
 identity.icon.tooltip=Show site information
 identity.extension.label=Extension (%S)
 identity.extension.tooltip=Loaded by extension: %S
 identity.showDetails.tooltip=Show connection details
-identity.hideDetails.tooltip=Hide connection details
 
 trackingProtection.intro.title=How Tracking Protection works
 # LOCALIZATION NOTE (trackingProtection.intro.description2):
 # %S is brandShortName. This string should match the one from Step 1 of the tour
 # when it starts from the button shown when a new private window is opened.
 trackingProtection.intro.description2=When you see the shield, %S is blocking some parts of the page that could track your browsing activity.
 # LOCALIZATION NOTE (trackingProtection.intro.step1of3): Indicates that the intro panel is step one of three in a tour.
 trackingProtection.intro.step1of3=1 of 3

--- a/browser/themes/shared/controlcenter/panel.inc.css
+++ b/browser/themes/shared/controlcenter/panel.inc.css
@@ -50,38 +50,27 @@
 }
 
 /* Make sure hidden elements don't accidentally become visible from one of the
    above selectors (see Bug 1194258) */
 #identity-popup [hidden] {
   display: none !important;
 }
 
-#identity-popup,
-#identity-popup:not([panelopen]) .panel-viewstack[viewtype="main"]:not([transitioning]) #identity-popup-mainView {
-  /* Tiny hack to ensure the panel shrinks back to its original
-     size after closing a subview that is bigger than the main view. */
-  max-height: 0;
-}
-
-.panel-mainview[panelid=identity-popup][viewtype=subview] > #identity-popup-mainView menulist,
-.panel-mainview[panelid=identity-popup][viewtype=subview] > #identity-popup-mainView button:not([panel-multiview-anchor]) {
-  -moz-user-focus: ignore;
-}
-
 #identity-popup > .panel-arrowcontainer > .panel-arrowcontent {
   padding: 0;
   /* Set default fill for icons in the identity popup.
      Individual icons can override this. */
   fill: currentColor;
   fill-opacity: .6;
 }
 
-.panel-mainview[panelid=identity-popup] {
+#identity-popup-mainView {
   min-width: 30em;
+  max-width: 30em;
 }
 
 #identity-popup-multiView > .panel-viewcontainer > .panel-viewstack[viewtype="main"] > .panel-subviews {
   transform: translateX(100%);
   box-shadow: none;
 }
 
 #identity-popup-multiView > .panel-viewcontainer > .panel-viewstack[viewtype="main"] > .panel-subviews:-moz-locale-dir(rtl) {
@@ -92,36 +81,29 @@
   background: var(--arrowpanel-background);
   padding: 0;
 }
 
 .identity-popup-section:not(:first-child) {
   border-top: 1px solid var(--panel-separator-color);
 }
 
-#identity-popup-securityView,
-#identity-popup-security-content,
+.identity-popup-security-content,
 #identity-popup-permissions-content,
 #tracking-protection-content {
   background-repeat: no-repeat;
   background-position: 1em 1em;
   background-size: 24px auto;
-}
-
-#identity-popup-security-content,
-#identity-popup-permissions-content,
-#tracking-protection-content {
   padding: 0.5em 0 1em;
   /* .identity-popup-host depends on this width */
   padding-inline-start: calc(2em + 24px);
   padding-inline-end: 1em;
 }
 
-#identity-popup-securityView:-moz-locale-dir(rtl),
-#identity-popup-security-content:-moz-locale-dir(rtl),
+.identity-popup-security-content:-moz-locale-dir(rtl),
 #identity-popup-permissions-content:-moz-locale-dir(rtl),
 #tracking-protection-content:-moz-locale-dir(rtl) {
   background-position: calc(100% - 1em) 1em;
 }
 
 /* EXPAND BUTTON */
 
 .identity-popup-expander {
@@ -133,53 +115,40 @@
   -moz-appearance: none;
   background: url("chrome://browser/skin/arrow-left.svg") center no-repeat;
   background-size: 16px, auto;
   -moz-context-properties: fill;
   fill: currentColor;
   color: inherit;
 }
 
-.identity-popup-expander[panel-multiview-anchor] {
-  transition: background-color 250ms ease-in;
-  background-color: Highlight;
-  background-image: url("chrome://browser/skin/arrow-left.svg");
-  color: HighlightText;
-}
-
-.identity-popup-expander[panel-multiview-anchor]:-moz-locale-dir(rtl),
-.identity-popup-expander:not([panel-multiview-anchor]):-moz-locale-dir(ltr) {
+.identity-popup-expander:-moz-locale-dir(ltr) {
   transform: scaleX(-1);
 }
 
 .identity-popup-expander > .button-box {
+  border-right: 1px solid var(--panel-separator-color);
   padding: 0;
 }
 
-.identity-popup-expander:not([panel-multiview-anchor]) > .button-box {
-  border-right: 1px solid var(--panel-separator-color);
-}
-
 .identity-popup-expander:hover {
   background-color: var(--arrowpanel-dimmed);
-  background-image: url("chrome://browser/skin/arrow-left.svg");
 }
 
 .identity-popup-expander:hover:active {
   background-color: var(--arrowpanel-dimmed-further);
   box-shadow: 0 1px 0 hsla(210,4%,10%,.05) inset;
 }
 
 /* CONTENT */
 
 .identity-popup-permission-label,
 .identity-popup-permission-state-label,
-#identity-popup-security-content > description,
+.identity-popup-security-content > description,
 #identity-popup-security-descriptions > description,
-#identity-popup-securityView-header > description,
 #identity-popup-securityView-body > description,
 #identity-popup-permissions-content > description,
 #tracking-protection-content > description {
   font-size: 110%;
   margin: 0;
 }
 
 /* This element needs the pre-wrap because we add newlines to it in the code. */
@@ -189,17 +158,17 @@
 
 .identity-popup-headline {
   margin: 3px 0 4px;
   font-size: 150%;
 }
 
 .identity-popup-host {
   word-wrap: break-word;
-  /* 1em + 2em + 24px is #identity-popup-security-content padding
+  /* 1em + 2em + 24px is .identity-popup-security-content padding
    * 30em is .panel-mainview width */
   max-width: calc(30rem - 3rem - 24px - @identityPopupExpanderWidth@);
 }
 
 .identity-popup-warning-gray {
   padding-inline-start: 24px;
   background: url(chrome://browser/skin/controlcenter/warning-gray.svg) no-repeat 0 50%;
 }
@@ -215,83 +184,62 @@
 }
 /* SECURITY */
 .identity-popup-connection-secure {
   color: #058B00;
 }
 .identity-popup-connection-not-secure {
   color: #d74345;
 }
-#identity-popup-securityView {
-  overflow: hidden;
-}
 
-#identity-popup-securityView,
-#identity-popup-security-content {
+.identity-popup-security-content {
   background-image: url(chrome://browser/skin/controlcenter/conn-not-secure.svg);
 }
 
-#identity-popup[connection=chrome] #identity-popup-securityView,
-#identity-popup[connection=chrome] #identity-popup-security-content {
+#identity-popup[connection=chrome] .identity-popup-security-content {
   background-image: url(chrome://branding/content/icon48.png);
 }
-#identity-popup[connection^=secure] #identity-popup-securityView,
-#identity-popup[connection^=secure] #identity-popup-security-content {
+#identity-popup[connection^=secure] .identity-popup-security-content {
   background-image: url(chrome://browser/skin/controlcenter/connection.svg);
   -moz-context-properties: fill;
   fill: #12BC00;
 }
 /* Use [isbroken] to make sure we don't show a lock on an http page. See Bug 1192162. */
-#identity-popup[ciphers=weak] #identity-popup-securityView,
-#identity-popup[ciphers=weak] #identity-popup-security-content,
-#identity-popup[mixedcontent~=passive-loaded][isbroken] #identity-popup-securityView,
-#identity-popup[mixedcontent~=passive-loaded][isbroken] #identity-popup-security-content {
+#identity-popup[ciphers=weak] .identity-popup-security-content,
+#identity-popup[mixedcontent~=passive-loaded][isbroken] .identity-popup-security-content {
   background-image: url(chrome://browser/skin/controlcenter/connection.svg);
   -moz-context-properties: fill, fill-opacity;
 }
 
-#identity-popup[connection=secure-cert-user-overridden] #identity-popup-securityView,
-#identity-popup[connection=secure-cert-user-overridden] #identity-popup-security-content {
+#identity-popup[connection=secure-cert-user-overridden] .identity-popup-security-content {
   background-image: url(chrome://browser/skin/connection-mixed-passive-loaded.svg);
   -moz-context-properties: fill, fill-opacity;
 }
 
-#identity-popup[loginforms=insecure] #identity-popup-securityView,
-#identity-popup[loginforms=insecure] #identity-popup-security-content,
-#identity-popup[mixedcontent~=active-loaded][isbroken] #identity-popup-securityView,
-#identity-popup[mixedcontent~=active-loaded][isbroken] #identity-popup-security-content {
+#identity-popup[loginforms=insecure] .identity-popup-security-content,
+#identity-popup[mixedcontent~=active-loaded][isbroken] .identity-popup-security-content {
   background-image: url(chrome://browser/skin/controlcenter/mcb-disabled.svg);
   -moz-context-properties: fill, fill-opacity;
 }
 
-#identity-popup[connection=extension] #identity-popup-securityView,
-#identity-popup[connection=extension] #identity-popup-security-content {
+#identity-popup[connection=extension] .identity-popup-security-content {
   background-image: url(chrome://browser/skin/controlcenter/extension.svg);
   -moz-context-properties: fill;
   fill: #60bf4c;
 }
 
 #identity-popup-security-descriptions > description {
   margin-top: 6px;
   color: Graytext;
 }
 
-#identity-popup-securityView-header,
 #identity-popup-securityView-body {
   margin-inline-start: calc(2em + 24px);
   margin-inline-end: 1em;
-}
-
-#identity-popup-securityView-header {
-  margin-top: 0.5em;
-  border-bottom: 1px solid var(--panel-separator-color);
-  padding-bottom: 1em;
-}
-
-#identity-popup-securityView-body {
+  border-top: 1px solid var(--panel-separator-color);
   padding-inline-end: 1em;
 }
 
 #identity-popup-securityView-footer {
   margin-top: 1em;
   background-color: var(--arrowpanel-dimmed);
 }