diff --git a/theme/index.hbs b/theme/index.hbs
index 625d6443be66..8be38847c76b 100644
--- a/theme/index.hbs
+++ b/theme/index.hbs
@@ -289,7 +289,6 @@
 
                 <!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
                 <script>
-                    document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
                     document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
                     Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
                         link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
diff --git a/theme/speaker-notes.js b/theme/speaker-notes.js
index 6247ea3ffa28..2251660caaa4 100644
--- a/theme/speaker-notes.js
+++ b/theme/speaker-notes.js
@@ -110,6 +110,8 @@
     popOutLocation.hash = "#speaker-notes-open";
     let popOut = document.createElement("button");
     popOut.classList.add("icon-button", "pop-out");
+    popOut.setAttribute("title", "Open speaker notes in a new window");
+    popOut.setAttribute("aria-label", "Open speaker notes in a new window");
     popOut.addEventListener("click", (event) => {
       let popup = window.open(popOutLocation.href, "speakerNotes", "popup");
       if (popup) {