wp_link_manager_disabled_message() WordPress Function

function wp_link_manager_disabled_message() {
	global $pagenow;

	if ( ! in_array( $pagenow, array( 'link-manager.php', 'link-add.php', 'link.php' ), true ) ) {
		return;
	}

	add_filter( 'pre_option_link_manager_enabled', '__return_true', 100 );
	$really_can_manage_links = current_user_can( 'manage_links' );
	remove_filter( 'pre_option_link_manager_enabled', '__return_true', 100 );

	if ( $really_can_manage_links ) {
		$plugins = get_plugins();

		if ( empty( $plugins['link-manager/link-manager.php'] ) ) {
			if ( current_user_can( 'install_plugins' ) ) {
				$install_url = wp_nonce_url(
					self_admin_url( 'update.php?action=install-plugin&plugin=link-manager' ),
					'install-plugin_link-manager'
				);

				wp_die(
					sprintf(
						/* translators: %s: A link to install the Link Manager plugin. */
						__( 'If you are looking to use the link manager, please install the <a href="%s">Link Manager plugin</a>.' ),
						esc_url( $install_url )
					)
				);
			}
		} elseif ( is_plugin_inactive( 'link-manager/link-manager.php' ) ) {
			if ( current_user_can( 'activate_plugins' ) ) {
				$activate_url = wp_nonce_url(
					self_admin_url( 'plugins.php?action=activate&plugin=link-manager/link-manager.php' ),
					'activate-plugin_link-manager/link-manager.php'
				);

				wp_die(
					sprintf(
						/* translators: %s: A link to activate the Link Manager plugin. */
						__( 'Please activate the <a href="%s">Link Manager plugin</a> to use the link manager.' ),
						esc_url( $activate_url )
					)
				);
			}
		}
	}

	wp_die( __( 'Sorry, you are not allowed to edit the links for this site.' ) );
}