Remove "(optional)" From Checkout Field Labels

Hides the "(optional)" text WooCommerce adds after the labels of fields that are not required.

Code

add_filter( 'woocommerce_form_field', function ( $field ) {
    return preg_replace( '#\s*<span class="optional">.*?</span>#', '', $field );
} );

Required fields still show their asterisk.

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