diff --git a/_static/activate_tab.js b/_static/activate_tab.js
new file mode 100644
index 0000000000..8b5fcbabd9
--- /dev/null
+++ b/_static/activate_tab.js
@@ -0,0 +1,42 @@
+// Based on https://stackoverflow.com/a/38241481/724176
+function getOS() {
+  const userAgent = window.navigator.userAgent,
+    platform =
+      window.navigator?.userAgentData?.platform || window.navigator.platform,
+    macosPlatforms = ["macOS", "Macintosh", "MacIntel", "MacPPC", "Mac68K"],
+    windowsPlatforms = ["Win32", "Win64", "Windows", "WinCE"],
+    iosPlatforms = ["iPhone", "iPad", "iPod"];
+
+  if (macosPlatforms.includes(platform)) {
+    return "macOS";
+  } else if (iosPlatforms.includes(platform)) {
+    return "iOS";
+  } else if (windowsPlatforms.includes(platform)) {
+    return "Windows";
+  } else if (/Android/.test(userAgent)) {
+    return "Android";
+  } else if (/Linux/.test(platform)) {
+    return "Unix";
+  }
+
+  return "unknown";
+}
+
+function activateTab(tabName) {
+  // Find all label elements containing the specified tab name
+  const labels = document.querySelectorAll(".tab-label");
+
+  labels.forEach((label) => {
+    if (label.textContent.includes(tabName)) {
+      // Find the associated input element using the 'for' attribute
+      const tabInputId = label.getAttribute("for");
+      const tabInput = document.getElementById(tabInputId);
+
+      // Check if the input element exists before attempting to set the "checked" attribute
+      if (tabInput) {
+        // Activate the tab by setting its "checked" attribute to true
+        tabInput.checked = true;
+      }
+    }
+  });
+}
diff --git a/conf.py b/conf.py
index c0997f017e..31ce4f5fd6 100644
--- a/conf.py
+++ b/conf.py
@@ -45,6 +45,9 @@
 html_css_files = [
     'devguide_overrides.css',
 ]
+html_js_files = [
+    "activate_tab.js",
+]
 html_logo = "_static/python-logo.svg"
 html_favicon = "_static/favicon.png"
 
diff --git a/index.rst b/index.rst
index 987f6b4bc3..0621180e75 100644
--- a/index.rst
+++ b/index.rst
@@ -2,6 +2,14 @@
 Python Developer's Guide
 ========================
 
+.. raw:: html
+
+    <script>
+    document.addEventListener('DOMContentLoaded', function() {
+      activateTab(getOS());
+    });
+    </script>
+
 .. highlight:: bash
 
 This guide is a comprehensive resource for :ref:`contributing <contributing>`
diff --git a/testing/run-write-tests.rst b/testing/run-write-tests.rst
index 58e56297d0..6fa9b04a58 100644
--- a/testing/run-write-tests.rst
+++ b/testing/run-write-tests.rst
@@ -5,6 +5,14 @@
 Running and writing tests
 =========================
 
+.. raw:: html
+
+    <script>
+    document.addEventListener('DOMContentLoaded', function() {
+      activateTab(getOS());
+    });
+    </script>
+
 .. note::
 
     This document assumes you are working from an