diff --git a/docusaurus.config.ts b/docusaurus.config.ts
index 21d6838..0a9763a 100644
--- a/docusaurus.config.ts
+++ b/docusaurus.config.ts
@@ -134,14 +134,17 @@ const config: Config = {
             {
               label: 'Home',
               href: 'https://defined.net',
+              rel: 'noopener',
             },
             {
               label: 'Blog',
               href: 'https://defined.net/blog',
+              rel: 'noopener',
             },
             {
               label: 'Docs',
               href: 'https://docs.defined.net',
+              rel: 'noopener',
             },
           ],
         },
diff --git a/package.json b/package.json
index f8c05a2..48531c3 100644
--- a/package.json
+++ b/package.json
@@ -16,6 +16,7 @@
   "dependencies": {
     "@docusaurus/core": "3.9.2",
     "@docusaurus/preset-classic": "3.9.2",
+    "@docusaurus/theme-common": "3.9.2",
     "@mdx-js/react": "^3.1.1",
     "clsx": "^2.1.1",
     "parse-domain": "^8.2.2",
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 5b55f15..4643371 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -14,6 +14,9 @@ importers:
       '@docusaurus/preset-classic':
         specifier: 3.9.2
         version: 3.9.2(@algolia/client-search@5.41.0)(@mdx-js/react@3.1.1(@types/react@19.2.2)(react@19.2.4))(@types/react@19.2.2)(react-dom@19.2.4(react@19.2.4))(react@19.2.4)(search-insights@2.17.0)(typescript@5.9.3)
+      '@docusaurus/theme-common':
+        specifier: 3.9.2
+        version: 3.9.2(@docusaurus/plugin-content-docs@3.9.2(@mdx-js/react@3.1.1(@types/react@19.2.2)(react@19.2.4))(react-dom@19.2.4(react@19.2.4))(react@19.2.4)(typescript@5.9.3))(react-dom@19.2.4(react@19.2.4))(react@19.2.4)
       '@mdx-js/react':
         specifier: ^3.1.1
         version: 3.1.1(@types/react@19.2.2)(react@19.2.4)
@@ -7151,7 +7154,7 @@ snapshots:
       '@babel/preset-env': 7.28.5(@babel/core@7.28.5)
       '@babel/preset-react': 7.28.5(@babel/core@7.28.5)
       '@babel/preset-typescript': 7.28.5(@babel/core@7.28.5)
-      '@babel/runtime': 7.28.4
+      '@babel/runtime': 7.28.6
       '@babel/runtime-corejs3': 7.28.4
       '@babel/traverse': 7.28.5
       '@docusaurus/logger': 3.9.2
@@ -9980,7 +9983,7 @@ snapshots:
 
   history@4.10.1:
     dependencies:
-      '@babel/runtime': 7.28.4
+      '@babel/runtime': 7.28.6
       loose-envify: 1.4.0
       resolve-pathname: 3.0.0
       tiny-invariant: 1.3.3
@@ -11774,13 +11777,13 @@ snapshots:
 
   react-loadable-ssr-addon-v5-slorber@1.0.1(@docusaurus/react-loadable@6.0.0(react@19.2.4))(webpack@5.102.1):
     dependencies:
-      '@babel/runtime': 7.28.4
+      '@babel/runtime': 7.28.6
       react-loadable: '@docusaurus/react-loadable@6.0.0(react@19.2.4)'
       webpack: 5.102.1
 
   react-router-config@5.1.1(react-router@5.3.4(react@19.2.4))(react@19.2.4):
     dependencies:
-      '@babel/runtime': 7.28.4
+      '@babel/runtime': 7.28.6
       react: 19.2.4
       react-router: 5.3.4(react@19.2.4)
 
@@ -11797,7 +11800,7 @@ snapshots:
 
   react-router@5.3.4(react@19.2.4):
     dependencies:
-      '@babel/runtime': 7.28.4
+      '@babel/runtime': 7.28.6
       history: 4.10.1
       hoist-non-react-statics: 3.3.2
       loose-envify: 1.4.0
diff --git a/src/theme/MDXComponents/A/index.tsx b/src/theme/MDXComponents/A/index.tsx
new file mode 100644
index 0000000..251069c
--- /dev/null
+++ b/src/theme/MDXComponents/A/index.tsx
@@ -0,0 +1,31 @@
+import Link from '@docusaurus/Link';
+import { useAnchorTargetClassName } from '@docusaurus/theme-common';
+import type { Props } from '@theme/MDXComponents/A';
+import clsx from 'clsx';
+import React, { type ReactNode } from 'react';
+
+export default function MDXA(props: Props): ReactNode {
+  // MDX Footnotes have ids such as <a id="user-content-fn-1-953011" ...>
+  const anchorTargetClassName = useAnchorTargetClassName(props.id);
+
+  // Customize rel attribute for *.defined.net links
+  let customRel = props.rel;
+  let customTarget = props.target;
+  if (props.href && typeof props.href === 'string') {
+    try {
+      const url = new URL(props.href, window.location.href);
+      // Check if it's an external link to *.defined.net
+      if (url.hostname.endsWith('.defined.net') || url.hostname === 'defined.net') {
+        // Override to only use 'noopener' (exclude 'noreferrer')
+        customRel = 'noopener';
+        customTarget = '_blank';
+      }
+    } catch {
+      // Invalid URL, let default behavior handle it
+    }
+  }
+
+  return (
+    <Link {...props} rel={customRel} target={customTarget} className={clsx(anchorTargetClassName, props.className)} />
+  );
+}