WordPress at Your Fingertips
filter is not described

twentynineteen_custom_colors_lightness filter-hook . WC 1.0

Usage

add_filter( 'twentynineteen_custom_colors_lightness', 'filter_function_name_1200' );
function filter_function_name_1200( $33 ){
	// filter...

	return $33;
}
$33
-

Where the hook is called

WC_Twenty_Nineteen::custom_colors_css()
twentynineteen_custom_colors_lightness
woocommerce/includes/theme-support/class-wc-twenty-nineteen.php 112
$lightness = absint( apply_filters( 'twentynineteen_custom_colors_lightness', 33 ) );

Where in WP core the hook is used WooCommerce

Usage not found.