Admin: Improve completion of first URL when enabling multiple URLs - refs GH#3516

public/main/admin/access_url_edit.php

@@ -41,6 +41,13 @@ if (isset($_GET['url_id'])) {
     }
     $url_data = UrlManager::get_url_data_from_id($url_id);
     $form->addElement('hidden', 'id', $url_data['id']);
+    // If we're still with localhost (should only happen at the very beginning)
+    // offer the current URL by default. Once this has been saved, no more
+    // magic will happen, ever.
+    if ($url_data['id'] === 1 && $url_data['url'] === 'http://localhost/') {
+        $https = api_is_https() ? 'https://' : 'http://';
+        $url_data['url'] = $https.$_SERVER['HTTP_HOST'].'/';
+    }
     $form->setDefaults($url_data);
     $submit_name = get_lang('Add URL');
 }