diff --git a/class-MenuEntry.php b/class-MenuEntry.php
index b517717..96b2507 100644
--- a/class-MenuEntry.php
+++ b/class-MenuEntry.php
@@ -1,155 +1,155 @@
 <?php
 # Copyright (C) 2015, 2018, 2019 Valerio Bozzolan
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 3 of the License, or
 # (at your option) any later version.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of
 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 # GNU General Public License for more details.
 #
 # You should have received a copy of the GNU General Public License
 # along with this program. If not, see <http://www.gnu.org/licenses/>.
 
 /**
  * Define a menu entry
  *
  * Some menu entries define a menu tree and can be displayed later.
  */
 class MenuEntry {
 
 	/**
 	 * Menu user identifier
 	 *
 	 * e.g. 'home'
 	 *
 	 * @var string
 	 */
 	public $uid;
 
 	/**
 	 * Identifier of the parent menu
 	 *
 	 * @var array|string|null
 	 */
 	public $parentUid;
 
 	/**
 	 * URI of the menu
 	 *
 	 * @var string
 	 */
 	public $url;
 
 	/**
 	 * Menu title
 	 *
 	 * @var string
 	 */
 	public $name;
 
 	/**
 	 * Permission to show this menu
 	 *
 	 * @var string|boolean
 	 */
 	public $permission;
 
 	/**
 	 * Extra metadata
 	 */
 	public $extra;
 
 	/**
 	 * Constructor
 	 *
 	 * @param string         $uid        Menu user identifier e.g. 'home'
 	 * @param string         $url        Page URL e.g. 'home.html'
 	 * @param string         $name       Page name
 	 * @param string         $parent_uid Parent menu user identifier
 	 * @param string|boolean $permission Permission required to see this page (true: always, false: never, string: check the permission name)
 	 * @param string         $extram     Extra metadata
 	 */
 	function __construct( $uid, $url = null, $name = null, $parent_uid = null, $permission = true, $extra = null ) {
 		$this->uid        = $uid;
 		$this->url        = $url;
 		$this->name       = $name;
 		$this->parentUid  = $parent_uid;
 
 		// backward compatibility
 		if( is_array( $permission ) ) {
-			error( "deprecated use of MenuEntry: now the #5 argument is \$permission and not $extra" );
+			error( "deprecated use of MenuEntry: now the #5 argument is \$permission and not \$extra" );
 			$extra = $permission;
 			$permission = null;
 		}
 
 		$this->permission = $permission;
 		$this->extra = $extra;
 	}
 
 	/**
 	 * Get the URL
 	 *
 	 * @param $absolute boolean
 	 * @return string
 	 * @see site_page()
 	 */
 	public function getURL( $absolute = false ) {
 		return site_page( $this->url, $absolute );
 	}
 
 	/**
 	 * Get an URL that should be absolute
 	 *
 	 * @return string
 	 * @see site_page()
 	 */
 	public function getAbsoluteURL() {
 		return $this->getURL( true );
 	}
 
 	/**
 	 * Check if the user has the permission to see this page
 	 *
 	 * @return boolean
 	 */
 	public function isVisible() {
 		if( is_string( $this->permission ) ) {
 			return has_permission( $this->permission );
 		}
 		return $this->permission;
 	}
 
 	/**
 	 * Get a metadata by name (alias)
 	 *
 	 * @param string $arg
 	 * @param $default
 	 * @return mixed
 	 */
 	public function get( $arg, $default = null ) {
 		if( isset( $this->extra[ $arg ] ) ) {
 			return $this->extra[ $arg ];
 		}
 		return $default;
 	}
 
 	/**
 	 * @deprecated
 	 */
 	public function getSitePage( $full_url = false ) {
 		error( "deprecated MenuEntry#getSitePage(), use getURL() instead" );
 		return $this->getURL( $full_url );
 	}
 
 	/**
 	 * @deprecated
 	 */
 	public function getExtra( $arg, $default = null ) {
 		error( "MenuEntry->getExtra() deprecated" );
 		return $this->get($arg, $default);
 	}
 }