? modules/overlay/overlay.css
Index: modules/overlay/overlay.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/overlay/overlay.module,v
retrieving revision 1.31
diff -u -p -r1.31 overlay.module
--- modules/overlay/overlay.module	31 Aug 2010 15:04:09 -0000	1.31
+++ modules/overlay/overlay.module	1 Sep 2010 19:23:53 -0000
@@ -30,6 +30,28 @@ function overlay_menu() {
     'access arguments' => array('access overlay'),
     'type' => MENU_CALLBACK,
   );
+  // disable the overlays directly without potentially opening an overlay
+  $items['overlay/disable/%'] = array(
+    'type' => MENU_CALLBACK,
+    'access arguments' => array('access overlay'),
+    'page callback' => 'overlay_user_disable',
+    'page arguments' => array(2),
+  );
+  // dismiss the accessibility message
+  $items['overlay/message-dismiss/%'] = array(
+    'type' => MENU_CALLBACK,
+    'access arguments' => array('access overlay'),
+    'page callback' => 'overlay_user_message_dismiss',
+    'page arguments' => array(2),
+  );
+  // provide a dedicated explanatory page
+  $items['overlay/accessibility-explanation'] = array(
+    'title' => 'Administrative overlays and accessibility',
+    'type' => MENU_CALLBACK,
+    'access arguments' => array('access overlay'),
+    'page callback' => 'overlay_accessibility_page',
+    'page arguments' => array(2),
+  );
   return $items;
 }
 
@@ -253,14 +275,94 @@ function overlay_page_alter(&$page) {
       $page[$skipped_region]['#access'] = FALSE;
     }
   }
-
   if (overlay_get_mode() == 'child') {
     // Add the overlay wrapper before the html wrapper.
     array_unshift($page['#theme_wrappers'], 'overlay');
   }
+  else {
+    global $user;
+    $use_overlay = !isset($user->data['overlay']) || $user->data['overlay'];
+    if (user_access('access overlay') && $use_overlay) {
+      // @todo: no UI for "revoking" the dismissal. Once dismissed situations can occur in which the overlays will have to used to disable the overlays
+      $dismissed = isset($user->data['overlay_message_dismissed']) && $user->data['overlay_message_dismissed'];
+      // show the disabled disable overlay link only if
+      // - the message has not been dismissed
+      // - the user is not on the explanatory page
+      // - the user is on a page on which links open in overlays (e.g. typing user/X/edit into a browser gets you onto a page that does not open links in overlays)
+      if ( !$dismissed && $_GET['q'] != 'overlay/accessibility-explanation' && overlay_get_mode() == 'parent') {
+        // Insert the link at the top and wrap it in a <div> to keep it similar to "skip-link"
+        // @todo: .element-invisible will need to be replaced/fixed cf. "Make .element-invisible work for focusable elements like links" (http://drupal.org/node/897638)
+        $page['page_top']['disable_overlay'] = array(
+          '#markup' => '<div class="element-invisible" id="disable-overlay">' . l(t('Click here if you have problems accessing the administrative pages (opening in Administrative overlays) or you want to dismiss this message.'), 'overlay/accessibility-explanation', array('query' => drupal_get_destination())) . '</div>',
+          '#weight' => -99
+        );
+      }
+    }
+  }
 }
 
 /**
+ * Menu callback disabling the overlay and redirecting back to the last page.
+ * If no destination was given, this redirects to the user edit page.
+ */
+function overlay_user_disable($token) {
+  if ($token == drupal_get_token('overlay')) {
+    global $user;
+    user_save(user_load($user->uid), array('data' => array('overlay' => 0)));
+    drupal_set_message(
+      t('The administrative overlay has been disabled. !user_profile_link',
+        array('!user_profile_link' => l( t('You can (re-)enable the overlay by editing your User Profile.'), 'user/' . $user->uid . '/edit' ) )
+      )
+    );
+    drupal_goto('user/' . $user->uid . '/edit');
+  }
+  else {
+    drupal_access_denied();
+  }
+}
+
+/**
+ * Menu callback dismissing the accessibility messag redirecting back to the last page.
+ * If no destination was given, this redirects to the user edit page.
+ */
+function overlay_user_message_dismiss($token) {
+  if ($token == drupal_get_token('overlay')) {
+    global $user;
+    user_save(user_load($user->uid), array('data' => array('overlay_message_dismissed' => 1)));
+    drupal_set_message(t('The message displayed at the top of the page has been dismissed.'));
+    drupal_goto('user/' . $user->uid . '/edit');
+  }
+  else {
+    drupal_access_denied();
+  }
+}
+
+/**
+ * Page explaining accessibility issues/concerns of overlays. Links to disabling overlays, dismissing message (and when overlays disabled link to user profile)
+ */
+function overlay_accessibility_page() {
+  global $user;
+  $text = t('Explain here in detail what this whole thing is and why it may interfere.');
+  $use_overlay = !isset($user->data['overlay']) || $user->data['overlay'];
+  $links = array();
+  if ( $use_overlay ) {
+    $links[] = array('title' => t('Disable the Administrative overlay.'), 'href' => 'overlay/disable/' . drupal_get_token('overlay'), 'query' => drupal_get_destination());
+    $dismissed = isset($user->data['overlay_message_dismissed']) && $user->data['overlay_message_dismissed'];
+    if (!$dismissed) {
+      $links[] = array('title' => t('Dismiss the message displayed at the top of pages.'), 'href' => 'overlay/message-dismiss/' . drupal_get_token('overlay'), 'query' => drupal_get_destination());
+    }
+  }
+  else {
+    // the overlay is not active therefore the user profile will not open in an overlay and be accessible
+    $links[] = array('title' => t('Enable the Administrative overlay from your User Profile.'), 'href' => 'user/' . $user->uid . '/edit');
+  }
+  // @todo: theming?
+  $text .= theme('links', array('links' => $links));
+  return $text;
+}
+
+
+/**
  * Implements hook_block_list_alter().
  */
 function overlay_block_list_alter(&$blocks) {