mce_buttons filter-hook . WP 1.0

This filter is documented in wp-includes/class-wp-editor.php

Usage

add_filter( 'mce_buttons', 'filter_function_name_2682', 10, 2 );
function filter_function_name_2682( $toolbar1, $string ){
	// filter...

	return $toolbar1;
}

$toolbar1

-

$string

-

Where the hook is called

$toolbar1 = apply_filters( 'mce_buttons', $toolbar1, 'classic-block' );

$mce_buttons = apply_filters( 'mce_buttons', $mce_buttons, $editor_id );

Where in WP core the hook is used WordPress