Post Network installation error

I would like to include Post Network in a site I am working on. I am using WordPress on a DreamHost site. WordPress version 6.1.1, PHP 8.0.

Has anyone seen this problem? Is there a fix? When I try to activate the plugin I get this error (replacing my domain with mysite.com):

Fatal error: Uncaught Error: Using $this when not in object context in /home/dh_7zqbrb/mysite.com/wp-content/plugins/post-network/includes/admin.php:536 Stack trace:
#0 /home/dh_7zqbrb/mysite.com/wp-content/plugins/post-network/post-network.php(53): PostNetwork::pn_option_init()
#1 /home/dh_7zqbrb/mysite.com/wp-includes/class-wp-hook.php(308): pn_activation(”)
#2 /home/dh_7zqbrb/mysite.com/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters(”, Array)
#3 /home/dh_7zqbrb/mysite.com/wp-includes/plugin.php(517): WP_Hook->do_action(Array)
#4 /home/dh_7zqbrb/mysite.com/wp-admin/plugins.php(194): do_action(‘activate_post-n…’)
#5 {main} thrown in /home/dh_7zqbrb/mysite.com/wp-content/plugins/post-network/includes/admin.php on line 536

The code at issue:

    public static function pn_option_init() {
$fields = $this->pn_get_fields(); # THIS LINE GIVES THE ERROR
$default_settings = array_column( $fields, ‘default’, ‘id’ );
update_option( self::$option_name, $default_settings );
}

Has anyone seen this problem? Is there a fix?