diff --git a/CHANGELOG.md b/CHANGELOG.md
index a366932a..05a7ae91 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@
 1. [](#bugfix)   
     * Fix for deeply nested sortable fields (at last!)
     * Restore admin session timeout modal by returning 401 for timed-out AJAX requests
+    * Honor `system.updates.safe_upgrade` so legacy Grav installs keep the classic updater
 
 # v1.10.49.1
 ## 09/03/2025
diff --git a/admin.php b/admin.php
index 8d04220f..52683621 100644
--- a/admin.php
+++ b/admin.php
@@ -385,6 +385,11 @@ class AdminPlugin extends Plugin
             'direct-install' => [['admin.super'], 'PLUGIN_ADMIN.DIRECT_INSTALL'],
         ]);
 
+        $config = $this->grav['config'] ?? null;
+        if (!SafeUpgradeManager::configAllowsSafeUpgrade($config)) {
+            return;
+        }
+
         try {
             $manifestFiles = glob(GRAV_ROOT . '/user/data/upgrades/*.json') ?: [];
 
diff --git a/classes/plugin/SafeUpgradeManager.php b/classes/plugin/SafeUpgradeManager.php
index 532a043e..fa506fde 100644
--- a/classes/plugin/SafeUpgradeManager.php
+++ b/classes/plugin/SafeUpgradeManager.php
@@ -14,6 +14,7 @@
 
 namespace Grav\Plugin\Admin;
 
+use Grav\Common\Config\Config;
 use Grav\Common\Filesystem\Folder;
 use Grav\Common\GPM\Installer;
 use Grav\Common\GPM\GPM;
@@ -1068,14 +1069,37 @@ class SafeUpgradeManager
     {
         try {
             $config = $this->grav['config'] ?? null;
-            if ($config === null) {
-                return true;
+            return self::configAllowsSafeUpgrade($config);
+        } catch (Throwable $e) {
+            return false;
+        }
+    }
+
+    /**
+     * @param Config|null $config
+     * @return bool
+     */
+    public static function configAllowsSafeUpgrade(?Config $config): bool
+    {
+        if ($config === null) {
+            return false;
+        }
+
+        $value = $config->get('system.updates.safe_upgrade');
+        if ($value === null) {
+            return false;
+        }
+
+        if (is_string($value)) {
+            $filtered = filter_var($value, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
+            if ($filtered === null) {
+                return false;
             }
 
-            return (bool)$config->get('system.updates.safe_upgrade', true);
-        } catch (Throwable $e) {
-            return true;
+            return $filtered;
         }
+
+        return (bool)$value;
     }
 
     /**
diff --git a/themes/grav/app/updates/index.js b/themes/grav/app/updates/index.js
index 43942fba..e970adff 100644
--- a/themes/grav/app/updates/index.js
+++ b/themes/grav/app/updates/index.js
@@ -10,12 +10,14 @@ import './update';
 import './channel-switcher';
 import SafeUpgrade from './safe-upgrade';
 
+const SAFE_UPGRADE_ENABLED = Number(config.safe_upgrade_enabled || 0) === 1;
+
 export default class Updates {
     constructor(payload = {}) {
         this.setPayload(payload);
         this.task = `task${config.param_sep}`;
         this.updateURL = '';
-        this.safeUpgrade = new SafeUpgrade(this);
+        this.safeUpgrade = SAFE_UPGRADE_ENABLED ? new SafeUpgrade(this) : null;
     }
 
     setPayload(payload = {}) {
diff --git a/themes/grav/js/admin.min.js b/themes/grav/js/admin.min.js
index 514c76c5..0d0ff9ef 100644
--- a/themes/grav/js/admin.min.js
+++ b/themes/grav/js/admin.min.js
@@ -3055,6 +3055,7 @@ function updates_toPrimitive(t, r) { if ("object" != updates_typeof(t) || !t) re
 
 
 
+var SAFE_UPGRADE_ENABLED = Number(external_GravAdmin_namespaceObject.config.safe_upgrade_enabled || 0) === 1;
 var Updates = /*#__PURE__*/function () {
   function Updates() {
     var payload = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : {};
@@ -3062,7 +3063,7 @@ var Updates = /*#__PURE__*/function () {
     this.setPayload(payload);
     this.task = "task".concat(external_GravAdmin_namespaceObject.config.param_sep);
     this.updateURL = '';
-    this.safeUpgrade = new SafeUpgrade(this);
+    this.safeUpgrade = SAFE_UPGRADE_ENABLED ? new SafeUpgrade(this) : null;
   }
   return updates_createClass(Updates, [{
     key: "setPayload",
diff --git a/themes/grav/templates/partials/base-root.html.twig b/themes/grav/templates/partials/base-root.html.twig
index 970b07e0..6aaf81e6 100644
--- a/themes/grav/templates/partials/base-root.html.twig
+++ b/themes/grav/templates/partials/base-root.html.twig
@@ -82,7 +82,8 @@
                 </div>
                 {% endblock %}
 
-                {% block modals %}
+{% set safe_upgrade_enabled = config.system.updates.safe_upgrade|default(false) %}
+{% block modals %}
                 {# Session expired blocking modal #}
                 <div class="remodal" data-remodal-id="session-expired" data-remodal-options="hashTracking: false">
                     <form>
@@ -127,6 +128,7 @@
                         </div>
                     </form>
                 </div>
+                {% if safe_upgrade_enabled %}
                 <div class="remodal safe-upgrade-modal" data-remodal-id="update-grav" data-remodal-options="hashTracking: false">
                     <form class="safe-upgrade-form">
                         <div class="safe-upgrade-header">
@@ -146,6 +148,21 @@
                         </div>
                     </form>
                 </div>
+                {% else %}
+                <div class="remodal" data-remodal-id="update-grav" data-remodal-options="hashTracking: false">
+                    <form>
+                        <h1>{{ "PLUGIN_ADMIN.MODAL_DELETE_FILE_CONFIRMATION_REQUIRED_TITLE"|t }}</h1>
+                        <p class="bigger">
+                            {{ "PLUGIN_ADMIN.MODAL_UPDATE_GRAV_CONFIRMATION_REQUIRED_DESC"|t }}
+                        </p>
+                        <br>
+                        <div class="button-bar">
+                            <button data-remodal-action="cancel" class="button secondary remodal-cancel"><i class="fa fa-fw fa-close"></i> {{ "PLUGIN_ADMIN.CANCEL"|t }}</button>
+                            <button data-remodal-action="confirm" class="button remodal-confirm disable-after-click"><i class="fa fa-fw fa-check"></i> {{ "PLUGIN_ADMIN.CONTINUE"|t }}</button>
+                        </div>
+                    </form>
+                </div>
+                {% endif %}
                 {% endblock %}
 
             </main>
diff --git a/themes/grav/templates/partials/javascript-config.html.twig b/themes/grav/templates/partials/javascript-config.html.twig
index 0d67af2c..77bdaffb 100644
--- a/themes/grav/templates/partials/javascript-config.html.twig
+++ b/themes/grav/templates/partials/javascript-config.html.twig
@@ -4,6 +4,7 @@
 {% set plugins_enabled = config.plugins.admin.notifications.plugins is same as(true) or config.plugins.admin.notifications.plugins == 'true' %}
 {% set themes_enabled = config.plugins.admin.notifications.themes is same as(true) or config.plugins.admin.notifications.themes == 'true' %}
 {% set notifications = (feed_enabled or dashboard_enabled or plugins_enabled or themes_enabled) ? 1 : 0 %}
+{% set safe_upgrade_enabled = config.system.updates.safe_upgrade|default(false) %}
 
 {% switch template_route %}
     {% case 'dashboard' %}
@@ -28,6 +29,7 @@
         {% endif %}
         admin_timeout: '{{ config.plugins.admin.session.timeout ?: 1800 }}',
         keep_alive_enabled: {{ (config.plugins.admin.session.keep_alive is defined ? config.plugins.admin.session.keep_alive : true) ? 1 : 0 }},
+        safe_upgrade_enabled: {{ safe_upgrade_enabled ? 1 : 0 }},
         admin_nonce: '{{ admin.getNonce }}',
         language: '{{ grav.user.language|default('en') }}',
         pro_enabled: '{{ config.plugins["admin-pro"].enabled }}',