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filter is not described

postbox_classes_(page)_(id) filter-hook . WP 3.2.0

Filters the postbox classes for a specific screen and screen ID combo.

The dynamic portions of the hook name, $page and $id, refer to the screen and screen ID, respectively.

Usage

add_filter( 'postbox_classes_(page)_(id)', 'filter_function_name_7846' );
function filter_function_name_7846( $classes ){
	// filter...

	return $classes;
}
$classes(array)
An array of postbox classes.

Where the hook is called

postbox_classes()
wp-admin/includes/post.php 1233
$classes = apply_filters( "postbox_classes_{$page}_{$id}", $classes );

Where the hook is used (in WP core)

wp-admin/includes/dashboard.php 30
add_filter( 'postbox_classes_dashboard_dashboard_browser_nag', 'dashboard_browser_nag_class' );