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filter is not described

nav_menu_attr_title filter-hook . WP 1.0

This filter is documented in wp-includes/nav-menu.php

Usage

add_filter( 'nav_menu_attr_title', 'filter_function_name_2922' );
function filter_function_name_2922( $attr_title ){
	// filter...

	return $attr_title;
}
$attr_title
-

Where the hook is called

WP_Customize_Nav_Menu_Item_Setting::value_as_wp_post_nav_menu_item()
nav_menu_attr_title
wp_setup_nav_menu_item()
nav_menu_attr_title
wp-includes/customize/class-wp-customize-nav-menu-item-setting.php 638
$post->attr_title = apply_filters( 'nav_menu_attr_title', $post->attr_title );
wp-includes/nav-menu.php 921
$menu_item->attr_title = ! isset( $menu_item->attr_title ) ? apply_filters( 'nav_menu_attr_title', $menu_item->post_excerpt ) : $menu_item->attr_title;
wp-includes/nav-menu.php 956
$menu_item->attr_title = apply_filters( 'nav_menu_attr_title', '' );

Where in WP core the hook is used WordPress

wp-includes/default-filters.php 148
add_filter( $filter, 'wptexturize' );
wp-includes/default-filters.php 149
add_filter( $filter, 'strip_tags' );