WordPress at a glance
filter is not described

pre_kses filter-hook . WP 2.3.0

Filters content to be run through kses.

Usage

add_filter( 'pre_kses', 'filter_function_name_395', 10, 3 );
function filter_function_name_395( $string, $allowed_html, $allowed_protocols ){
	// filter...

	return $string;
}
$string(string)
Content to run through KSES.
$allowed_html(array[]/string)
Allowed HTML elements.
$allowed_protocols(string[])
Array of allowed URL protocols.

Where the hook is called

wp_kses_hook()
pre_kses
wp-includes/kses.php 914
return apply_filters( 'pre_kses', $string, $allowed_html, $allowed_protocols );

Where the hook is used (in WP core)

wp-includes/default-filters.php 247
add_filter( 'pre_kses', 'wp_pre_kses_less_than' );