Index: modules/overlay/overlay.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/overlay/overlay.module,v
retrieving revision 1.22
diff -u -p -r1.22 overlay.module
--- modules/overlay/overlay.module	13 Jun 2010 05:47:47 -0000	1.22
+++ modules/overlay/overlay.module	24 Jun 2010 16:29:44 -0000
@@ -42,6 +42,10 @@ function overlay_permission() {
       'title' => t('Access the administrative overlay'),
       'description' => t('View administrative pages in the overlay.'),
     ),
+    'enable overlay' => array(
+      'title' => t('Enable the administrative overlay'),
+      'description' => t('Allow users to enable the overlay for their account.'),
+    ),
   );
 }
 
@@ -58,6 +62,27 @@ function overlay_theme() {
 }
 
 /**
+ * Implements hook_form_FORM_ID_alter().
+ */
+function overlay_form_user_profile_form_alter(&$form, &$form_state) {
+  if ($form['#user_category'] == 'account') {
+    $account = $form['#user'];
+    if (user_access('access overlay', $account) && user_access('enable overlay')) {
+      $form['account']['data'] = array('#tree' => TRUE);
+      $form['account']['data']['overlay'] = array(
+        '#type' => 'checkbox',
+        '#title' => t('Use overlay'),
+        '#default_value' => isset($account->data['overlay']) ? $account->data['overlay'] : 0,
+        '#description' => t('Open content creation and administrative pages in an overlay.'),
+        '#weight' => 10,
+      );
+      return $form;
+    }
+  }
+}
+
+
+/**
  * Implements hook_init().
  *
  * Determine whether the current page request is destined to appear in the
@@ -67,13 +92,14 @@ function overlay_theme() {
  */
 function overlay_init() {
   // @todo: custom_theme does not exist anymore.
-  global $custom_theme;
+  global $custom_theme, $user;
 
   $mode = overlay_get_mode();
 
   // Only act if the user has access to the overlay and a mode was not already
   // set. Other modules can also enable the overlay directly for other uses.
-  if (empty($mode) && user_access('access overlay')) {
+  $use_overlay = user_accesS('enable overlay') && isset($user->data['overlay']) && $user->data['overlay'];
+  if (empty($mode) && user_access('access overlay') && $use_overlay) {
     $current_path = current_path();
     // After overlay is enabled on the modules page, redirect to
     // <front>#overlay=admin/modules to actually enable the overlay.