diff --git a/_includes/footer.html b/_includes/footer.html
index 573db20f..3b84b65d 100644
--- a/_includes/footer.html
+++ b/_includes/footer.html
@@ -33,7 +33,7 @@ <h4 class="footer-title">Help Us Provide the Correct Answer</h4>
 <script defer src="/public/js/lightbox.js"></script>
 <script defer src="/public/js/wow.min.js"></script>
 
-{% if page.mermaid == true or page.content contains '```mermaid' %}
+{% if include.has_mermaid %}
 <script defer src="https://unpkg.com/mermaid@11/dist/mermaid.min.js"></script>
 {% endif %}
 
@@ -55,6 +55,6 @@ <h4 class="footer-title">Help Us Provide the Correct Answer</h4>
 </script>
 
 <!-- This is to avoid having to include widgets.js every time a tweet is embedded -->
-{% if page.content contains 'twitter-tweet' or page.content contains 'twitter-timeline' %}
+{% if include.has_twitter %}
 <script defer src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>
 {% endif %}
diff --git a/_includes/head.html b/_includes/head.html
index 2ce3663f..baafad29 100755
--- a/_includes/head.html
+++ b/_includes/head.html
@@ -81,7 +81,7 @@
 
   
   <!-- Enable responsiveness on mobile devices-->
-  <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1, user-scalable=no">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
   <!-- RSS -->
   <link rel="alternate" type="application/rss+xml" title="RSS" href="{{ '/atom.xml' | relative_url }}">
 
@@ -97,7 +97,7 @@
     {% endif %}
   </title>
 
-  <!--   <link rel="canonical" href="{{ site.baseurl }}/{{ page.permalink }}" /> -->
+  <link rel="canonical" href="{{ page.url | absolute_url }}" />
 
   <!-- CSS -->
 
diff --git a/_includes/header.html b/_includes/header.html
index 90d9e06b..e783f824 100644
--- a/_includes/header.html
+++ b/_includes/header.html
@@ -10,7 +10,7 @@
               width="45"
               height="45"
               alt="RetroReversing logo"
-              style="height: 45px; padding-right: 10px; margin-bottom: 10px;"
+              style="height: 45px; margin-right: 5px; margin-bottom: 10px;"
             />
             <a href="/" class="logo">Retro Reversing</a>
             <nav class="nav">
diff --git a/_includes/sources-sidebar.html b/_includes/sources-sidebar.html
index b9d5cc47..b77eca47 100644
--- a/_includes/sources-sidebar.html
+++ b/_includes/sources-sidebar.html
@@ -13,7 +13,7 @@ <h5 class="widget-title">Sources <span>({{ include.references.size }})</span></h
   </div>
 {% endif %}
 {% if include.hideTOC != true %}
-  <div class="post-directory widget widget-friends">
+  <div class="post-directory widget">
     <h2 class="widget-title">Table of Contents</h2>
     <nav class="post-directory-nav" aria-label="Table of contents">
       <ul class="post-directory-list"></ul>
diff --git a/_includes/video-header.html b/_includes/video-header.html
index 944f20fa..9e58a38b 100644
--- a/_includes/video-header.html
+++ b/_includes/video-header.html
@@ -3,7 +3,15 @@
     <div class="overlay-light"></div>
     <div class="container">
       <div class="embed-responsive embed-responsive-16by9">
-        <iframe class="embed-responsive-item" src="https://www.youtube.com/embed/{{ include.youtube }}" allowfullscreen></iframe>
+        <iframe
+          class="embed-responsive-item"
+          src="https://www.youtube-nocookie.com/embed/{{ include.youtube }}"
+          title="YouTube video"
+          loading="lazy"
+          referrerpolicy="strict-origin-when-cross-origin"
+          allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share"
+          allowfullscreen
+        ></iframe>
       </div>
     </div>
   </section>
diff --git a/_layouts/404.html b/_layouts/404.html
index 2d4e966d..15b8c90a 100644
--- a/_layouts/404.html
+++ b/_layouts/404.html
@@ -69,7 +69,7 @@ <h5 class="widget-title">Recently Updated</h5>
   </section>
   <!-- /main -->
 
-  {% include_cached footer.html %}
+  {% include_cached footer.html has_mermaid=false has_twitter=false %}
 
   <script>
     (function () {
diff --git a/_layouts/home.html b/_layouts/home.html
index 16e0871c..134237aa 100644
--- a/_layouts/home.html
+++ b/_layouts/home.html
@@ -60,7 +60,7 @@
   </section>
   <!-- /main -->
 
-  {% include_cached footer.html %}
+  {% include_cached footer.html has_mermaid=false has_twitter=false %}
  
 </body>
 </html>
diff --git a/_layouts/post.html b/_layouts/post.html
index 6614fd9d..e603b7a4 100755
--- a/_layouts/post.html
+++ b/_layouts/post.html
@@ -39,7 +39,16 @@
   </main>
   <!-- /main -->
 
-  {% include_cached footer.html %}
+  {% assign has_mermaid = false %}
+  {% if page.mermaid == true or page.content contains '```mermaid' or page.content contains 'language-mermaid' or page.content contains 'lang-mermaid' %}
+    {% assign has_mermaid = true %}
+  {% endif %}
+
+  {% assign has_twitter = false %}
+  {% if page.content contains 'twitter-tweet' or page.content contains 'twitter-timeline' %}
+    {% assign has_twitter = true %}
+  {% endif %}
+  {% include_cached footer.html has_mermaid=has_mermaid has_twitter=has_twitter %}
 
  
 </body>
diff --git a/pages/Industry/GDC.md b/pages/Industry/GDC.md
index 12ed0f5d..2932ae3a 100644
--- a/pages/Industry/GDC.md
+++ b/pages/Industry/GDC.md
@@ -22,11 +22,15 @@ excerpt: Awesome list of Historic GDC Conferences including Audio and Video reco
 updatedAt: '2024-11-23'
 ---
 
-# GDC - Game Developer's Conference
-<section class="postSection">
-    <img data-image-full="https://github.com/user-attachments/assets/d3665255-3b43-4787-819f-92a49fcd1030" class="lazy-load wow slideInLeft postImage" />
-
- <div markdown="1" class="rr-post-markdown">
+<img    class="wow slideInLeft postImage"
+        src="https://github.com/user-attachments/assets/d3665255-3b43-4787-819f-92a49fcd1030"
+        width="578"
+        height="325"
+        alt="Game Developers Conference (GDC)"
+        style="margin-bottom: 10px;"
+        decoding="async"
+        fetchpriority="high"
+    />
 
 GDC stands for the "Game Developers Conference", which is an annual event held for professionals in the video game industry. 
 
@@ -35,10 +39,6 @@ Originally it was called the **Computer Game Developers Conference** but the Com
 GDC serves as a hub for game developers, publishers, artists, programmers, designers, and other industry experts to come together to discuss, share, and learn about the latest trends, technologies, and practices in game development. 
 
 The event includes a wide range of sessions, panels, workshops, and networking opportunities.
- </div>
-</section> 
-
-
 
 
 ## CGDC 1988
diff --git a/pages/consoles/gameboy/Mrdo.md b/pages/consoles/gameboy/Mrdo.md
index 7b5dbf4d..cb1b937a 100644
--- a/pages/consoles/gameboy/Mrdo.md
+++ b/pages/consoles/gameboy/Mrdo.md
@@ -37,28 +37,27 @@ This video provides a brief look at the Game Boy port and is useful context befo
 <iframe width="560" height="315" src="https://www.youtube.com/embed/WniQSM86SP4" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe>
 
 ---
-# Source code release
+## Source code release
 The original release is a single monolithic assembly file (`mrdo.asm`) containing code, data tables, and large blocks of embedded graphics data [^2].
 
 Description from Paul Hughes [^1]:
 > Many moons ago I debugged and finished off Ocean's Mr Do! for the original Game Boy. 
 > 
-> As **Joffa**, the late, great original author, decided to release the source code, 
-> 
+> As **Joffa**, the late, great original author, decided to release the source code,
 > I thought I'd also put it up.
 
 The header for the source file also mentions Wesley Knackers and gives a start date of June 28, 1990 and a last date of September 5, 1990:
 
 ```cpp
 ****************************************************************************
-*									   *
-*		MR DO! (C) 1990 SPECIAL FX SOFTWARE LIMITED		   *
-*									   *
-*		           BY WESLEY KNACKERS				   *
-*									   *
-*		  	  START DATE 28/06/90				   *
-*		  	   LAST DATE 05/09/90				   *
-*									   *
+*									   
+*		MR DO! (C) 1990 SPECIAL FX SOFTWARE LIMITED		   
+*									   
+*		           BY WESLEY KNACKERS				   
+*									   
+*		  	  START DATE 28/06/90				   
+*		  	   LAST DATE 05/09/90				   
+*									   
 ****************************************************************************
 ```
 
@@ -80,8 +79,7 @@ If you are new to Game Boy reverse engineering terminology, this quick glossary
 
 ---
 # Code overview
-The source is useful because it is not a "disassembly" or a ROM dump.
-It is proper annotated game code with labels and routines that map closely onto the retail behaviour.
+The source is useful because it is not a "disassembly" or a ROM dump, it is a rare case of real Game Boy source code being released online for a commerical game.
 
 Some highlights worth skimming first:
 * **Main loop** - `START` runs `SYSETUP`, `MENU`, and then enters a per-level loop that calls the gameplay subsystems in a predictable order.
@@ -89,9 +87,6 @@ Some highlights worth skimming first:
 * **2x2 meta-tiles** - The map is built from 4-tile blocks (top-left/top-right/bottom-left/bottom-right) with additional tables for "eaten" wall variants.
 * **Split-screen rendering** - `SPLITSCREEN` does a status-window pass, then triggers OAM DMA for gameplay sprites after a timing delay.
 
----
-# Deeper file tour
-If you want to understand the game quickly, it helps to treat `mrdo.asm` as a handful of tightly-coupled subsystems that run in a strict per-frame pipeline.
 
 ## Frame pipeline
 The `MAINLOOP` order is deliberate.
diff --git a/public/css/post.css b/public/css/post.css
index 1712ccdb..dd3cca6d 100644
--- a/public/css/post.css
+++ b/public/css/post.css
@@ -472,12 +472,108 @@ h5 + .emoji {
 
 .post-directory-list li {
   list-style: none;
+  float: none;
+  width: 100%;
+  margin: 0;
+}
+
+.post-directory-list li.jumper--H1 {
+  margin-left: 0;
+  margin-top: 10px;
+}
+
+.post-directory-list li.jumper--H2 {
+  margin-left: 12px;
+}
+
+.post-directory-list li.jumper--H3 {
+  margin-left: 24px;
+}
+
+.post-directory-list li.jumper--H4 {
+  margin-left: 32px;
+}
+
+.post-directory-list li.jumper--H5 {
+  margin-left: 38px;
+}
+
+.post-directory-list li.jumper--H6 {
+  margin-left: 44px;
+}
+
+.post-directory-list li.jumper--H1 > a {
+  font-size: 1.02rem;
+  font-weight: 800;
+  color: #006d96;
+}
+
+.post-directory-list li.jumper--H2 > a {
+  font-size: 0.95rem;
+  font-weight: 700;
+  color: #0085b6;
+}
+
+.post-directory-list li.jumper--H1 + li.jumper--H1,
+.post-directory-list li.jumper--H2 + li.jumper--H2 {
+  margin-top: 8px;
+}
+
+.post-directory-list li.jumper--H3 > a {
+  font-size: 0.88rem;
+  font-weight: 500;
+}
+
+.post-directory-list li.jumper--H4 > a,
+.post-directory-list li.jumper--H5 > a,
+.post-directory-list li.jumper--H6 > a {
+  font-size: 0.84rem;
+  font-weight: 400;
+}
+
+.post-directory-list li.jumper--H3 > a,
+.post-directory-list li.jumper--H4 > a,
+.post-directory-list li.jumper--H5 > a,
+.post-directory-list li.jumper--H6 > a {
+  position: relative;
+  padding-left: 14px;
+}
+
+.post-directory-list li.jumper--H3 > a::before,
+.post-directory-list li.jumper--H4 > a::before,
+.post-directory-list li.jumper--H5 > a::before,
+.post-directory-list li.jumper--H6 > a::before {
+  content: "";
+  position: absolute;
+  left: 4px;
+  top: 50%;
+  transform: translateY(-50%);
+  width: 6px;
+  height: 1px;
+  background: rgba(0, 133, 182, 0.4);
 }
 
 .post-directory-list a {
   display: block;
-  padding: 6px 8px;
   border-radius: 6px;
+  text-decoration: none;
+}
+
+.post-directory-list li + li {
+  margin-top: 2px;
+}
+
+.post-directory .jumper {
+  margin: 0;
+}
+
+.post-directory a.jumper--child {
+  color: #848484;
+}
+
+.post-directory a.jumper--child:hover,
+.post-directory a.jumper--child:focus {
+  color: #0085b6;
 }
 
 .post-directory-list a:focus-visible {
@@ -487,7 +583,6 @@ h5 + .emoji {
 
 .reversefootnote {
   display: inline-block;
-  padding: 6px 8px;
   margin-left: 4px;
   border-radius: 6px;
 }
diff --git a/public/js/generateTOC.js b/public/js/generateTOC.js
index 5dd65fad..3492d0e0 100644
--- a/public/js/generateTOC.js
+++ b/public/js/generateTOC.js
@@ -19,7 +19,7 @@ $(document).ready(function(){
         if (!$list.length) return;
 
         if (tagName === topLevel) {
-            $list.append("<li><a class=\"jumper\" href=\"#" + id + "\">" + $this.text() + "</a></li>");
+            $list.append("<li class=\"jumper--"+tagName+"\"><a class=\"jumper\" href=\"#" + id + "\">" + $this.text() + "</a></li>");
         } else {
             $list.append("<li class=\"jumper--"+tagName+"\"><a class=\"jumper--child\" href=\"#" + id + "\">" + $this.text() + "</a></li>");
         }
diff --git a/public/js/main.js b/public/js/main.js
index 1e1a5276..2abf7bcc 100644
--- a/public/js/main.js
+++ b/public/js/main.js
@@ -452,15 +452,35 @@ document.addEventListener("DOMContentLoaded", function() {
     return;
   }
 
-  function runMermaid() {
-    initializeMermaidDiagrams();
+  function scheduleMermaidInit() {
+    if (typeof window.requestIdleCallback === "function") {
+      window.requestIdleCallback(function() {
+        initializeMermaidDiagrams();
+      }, { timeout: 2500 });
+    } else {
+      setTimeout(function() {
+        initializeMermaidDiagrams();
+      }, 0);
+    }
   }
 
-  if (typeof window.requestIdleCallback === "function") {
-    window.requestIdleCallback(runMermaid, { timeout: 2500 });
-  } else {
-    setTimeout(runMermaid, 2500);
+  function waitForMermaid(attemptsRemaining) {
+    if (typeof mermaid !== "undefined") {
+      scheduleMermaidInit();
+      return;
+    }
+
+    if (attemptsRemaining <= 0) {
+      return;
+    }
+
+    setTimeout(function() {
+      waitForMermaid(attemptsRemaining - 1);
+    }, 250);
   }
+
+  // Mermaid is loaded via a deferred external script; wait briefly for it to be available.
+  waitForMermaid(20);
 });
 
   function setupCarousel() {
@@ -502,9 +522,92 @@ document.addEventListener("DOMContentLoaded", function() {
     var $tablesToEnhance = $tables.filter(onlyRowsGreaterThanMinimum);
     if (!$tablesToEnhance.length) return;
 
+    function isEligibleForDataTable($table) {
+      // DataTables expects a reasonably well-formed table with a header row.
+      // Some pages have layout/diagram tables or mixed colspan/rowspan that break initialization.
+      var hasHeaderCells = $table.find('thead tr th').length > 0;
+      if (!hasHeaderCells) return false;
+
+      var hasComplexSpans = $table.find('th[colspan],th[rowspan],td[colspan],td[rowspan]').length > 0;
+      if (hasComplexSpans) return false;
+
+      // DataTables assumes a consistent column count across the header and body rows.
+      var $headerRows = $table.find('thead tr');
+      if ($headerRows.length !== 1) return false;
+
+      var $headerRow = $headerRows.first();
+      var headerColumnCount = $headerRow.children('th,td').length;
+      if (!headerColumnCount) return false;
+
+      var $bodyRows = $table.find('tbody tr');
+      if (!$bodyRows.length) {
+        $bodyRows = $table.find('tr').not($table.find('thead tr'));
+      }
+      if (!$bodyRows.length) return false;
+
+      var hasMismatchedColumns = false;
+      $bodyRows.each(function() {
+        if ($(this).children('th,td').length !== headerColumnCount) {
+          hasMismatchedColumns = true;
+          return false;
+        }
+      });
+      if (hasMismatchedColumns) return false;
+
+      return true;
+    }
+
     function initialize() {
       if (typeof $.fn.DataTable !== 'function') return;
-      $tablesToEnhance.DataTable();
+
+      if (!window.__rrDataTablesErrorHandlerInstalled) {
+        window.__rrDataTablesErrorHandlerInstalled = true;
+        window.addEventListener('error', function(event) {
+          var message = (event && event.message) ? String(event.message) : '';
+          var filename = (event && event.filename) ? String(event.filename) : '';
+          var isDataTablesError = message.indexOf('mData') !== -1 && filename.indexOf('datatables') !== -1;
+          if (!isDataTablesError) return;
+
+          try {
+            var lastTable = window.__rrLastDataTableTable;
+            if (lastTable && typeof $ !== 'undefined') {
+              // Prevent repeated attempts on a table that DataTables cannot parse.
+              lastTable.setAttribute('data-rr-datatable-disabled', 'true');
+              if ($.fn.dataTable && typeof $.fn.dataTable.isDataTable === 'function' && $.fn.dataTable.isDataTable(lastTable)) {
+                $(lastTable).DataTable().destroy();
+              }
+            }
+          } catch (e) {
+            // Swallow cleanup errors.
+          }
+
+          if (event && typeof event.preventDefault === 'function') {
+            event.preventDefault();
+          }
+        }, true);
+      }
+
+      $tablesToEnhance.each(function() {
+        var table = this;
+        var $table = $(table);
+        if (!isEligibleForDataTable($table)) return;
+        if (table.getAttribute('data-rr-datatable-disabled') === 'true') return;
+
+        if ($.fn.dataTable && typeof $.fn.dataTable.isDataTable === 'function' && $.fn.dataTable.isDataTable(table)) {
+          return;
+        }
+
+        try {
+          window.__rrLastDataTableTable = table;
+          $table.DataTable({
+            autoWidth: false,
+            deferRender: true
+          });
+        } catch (e) {
+          // If a single table is malformed, don't break the rest of the page.
+          console.warn('DataTables init skipped for a table:', e);
+        }
+      });
     }
 
     if (typeof $.fn.DataTable === 'function') {
diff --git a/robots.txt b/robots.txt
new file mode 100644
index 00000000..b764cf52
--- /dev/null
+++ b/robots.txt
@@ -0,0 +1,4 @@
+User-agent: *
+Allow: /
+
+Sitemap: https://www.retroreversing.com/sitemap.xml