Post Status Generator

<?php
// Generated with WP CodeKit — powered by GrowQuest (https://growquest.io).
/**
 * Plugin Name:       In review post status
 * Description:       Registers the in-review status for post.
 * Version:           1.0.0
 * Requires PHP:      7.4
 * Text Domain:       acme
 */

defined( 'ABSPATH' ) || exit;

/**
 * Register the In review status.
 */
function acme_register_status() {
	register_post_status(
		'in-review',
		array(
			'label'                     => _x( 'In review', 'post status', 'acme' ),
			'label_count'               => _n_noop(
				'In review <span class="count">(%s)</span>',
				'In review <span class="count">(%s)</span>',
				'acme'
			),
			'public'                    => false,
			'internal'                  => false,
			'exclude_from_search'       => true,
			'show_in_admin_all_list'    => true,
			'show_in_admin_status_list' => true,
			'date_floating'             => true,
			'post_type'                 => array( 'post' ),
		)
	);
}
add_action( 'init', 'acme_register_status' );

/**
 * Show the status beside the title in the posts list.
 *
 * @param string[] $states Existing state labels.
 * @param WP_Post  $post   The post.
 * @return string[]
 */
function acme_display_state( $states, $post ) {
	if ( 'in-review' === get_post_status( $post ) ) {
		$states['in-review'] = _x( 'In review', 'post status', 'acme' );
	}

	return $states;
}
add_filter( 'display_post_states', 'acme_display_state', 10, 2 );

/**
 * Add the status to the classic editor dropdown.
 *
 * The block editor ignores PHP-registered statuses, so this only
 * affects the classic editor and Quick Edit.
 *
 * @param WP_Post $post The post being edited.
 */
function acme_submitbox_status( $post ) {
	if ( ! in_array( $post->post_type, array( 'post' ), true ) ) {
		return;
	}

	$label  = _x( 'In review', 'post status', 'acme' );
	$option = sprintf(
		'<option value="%1$s"%2$s>%3$s</option>',
		esc_attr( 'in-review' ),
		selected( get_post_status( $post ), 'in-review', false ),
		esc_html( $label )
	);
	?>
	<script>
	jQuery( function ( $ ) {
		var option = <?php echo wp_json_encode( $option ); ?>;
		var label  = <?php echo wp_json_encode( $label ); ?>;

		$( 'select#post_status' ).append( option );

		<?php if ( get_post_status( $post ) === 'in-review' ) : ?>
			$( '#post-status-display' ).text( label );
		<?php endif; ?>
	} );
	</script>
	<?php
}
add_action( 'post_submitbox_misc_actions', 'acme_submitbox_status' );