diff --git a/CHANGELOG.md b/CHANGELOG.md
index 31d24e43..7c0d2847 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,6 +4,10 @@
 
 
 
+<h2>Version 4.0.0 - ??/??/2026</h2>
+      <ul>
+        <li>...</li>
+      </ul>
 <h2>Version 3.8.3 - 22/01/2026</h2>
       <ul>
         <li>Fix: Correctly saving the API settings in new custom prompts [<a href="https://github.com/micz/ThunderAI/issues/623">#623</a>].</li>
diff --git a/manifest.json b/manifest.json
index c70f8713..961a7d9e 100644
--- a/manifest.json
+++ b/manifest.json
@@ -2,7 +2,7 @@
     "manifest_version": 2,
     "name": "ThunderAI",
     "description": "__MSG_extensionDescription__",
-    "version": "3.8.3",
+    "version": "4.0.0",
     "author": "Mic (m@micz.it)",
     "homepage_url": "https://micz.it/thunderbird-addon-thunderai/",
     "browser_specific_settings": {
diff --git a/options/mzta-release-notes.html b/options/mzta-release-notes.html
index c87ef83c..6c27cd96 100644
--- a/options/mzta-release-notes.html
+++ b/options/mzta-release-notes.html
@@ -7,6 +7,10 @@
   <body>
     <div id="miczBackPrefs"><a href="mzta-options.html">__MSG_backToOptionsText__</a></div>
     <div id="miczRelNotes"><h1>ThunderAI Release Notes</h1>
+      <h2>Version 4.0.0 - ??/??/2026</h2>
+      <ul>
+        <li>...</li>
+      </ul>
       <h2>Version 3.8.3 - 22/01/2026</h2>
       <ul>
         <li>Fix: Correctly saving the API settings in new custom prompts [<a href="https://github.com/micz/ThunderAI/issues/623">#623</a>].</li>
