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filter is not described

list_cats filter-hook . WP 1.0

This filter is documented in wp-includes/category-template.php

Usage

add_filter( 'list_cats', 'filter_function_name_9020', 10, 2 );
function filter_function_name_9020( $name, $category ){
	// filter...

	return $name;
}
$name
-
$category
-

Where the hook is called

Walker_CategoryDropdown::start_el()
list_cats
wp_dropdown_categories()
list_cats
Walker_Category::start_el()
list_cats
wp-includes/class-walker-category-dropdown.php 61
$cat_name = apply_filters( 'list_cats', $category->name, $category );
wp-includes/category-template.php 427
$show_option_none = apply_filters( 'list_cats', $parsed_args['show_option_none'], null );
wp-includes/category-template.php 436
$show_option_all = apply_filters( 'list_cats', $parsed_args['show_option_all'], null );
wp-includes/category-template.php 444
$show_option_none = apply_filters( 'list_cats', $parsed_args['show_option_none'], null );
wp-includes/class-walker-category.php 100
$cat_name = apply_filters( 'list_cats', esc_attr( $category->name ), $category );

Where in WP core the hook is used WordPress

wp-includes/default-filters.php 203
add_filter( 'list_cats', 'wptexturize' );