Remove columns Support Ticket System Plugin

Hi,

I would like to remove some columns of the support ticket page of the plugin Support System.

I have this code already:

// Hide admin columns
function my_columns_filter( $columns ) {
    unset($columns['author']);
    unset($columns['wpseo-title']);
    unset($columns['comments']);
    unset($columns['tags']);
    unset($columns['meta']);
    unset($columns['wpseo-metadesc']);
    unset($columns['wpseo-focuskw']);
    unset($columns['description']);
    unset($columns['wpseo-score']);
    unset($columns['wpseo-score-readability']);
    unset($columns['status']); // Support System
    unset($columns['priority']); // Support System

    return $columns;
}
add_filter( 'manage_edit-post_columns', 'my_columns_filter', 10, 1 ); // Posts
add_filter( 'manage_edit-page_columns', 'my_columns_filter', 10, 1 ); // Pages

Problem is the columns are at this page:
/wp-admin/admin.php?page=ticket-manager

This is not a custom post type, so I don't know how to target this page with the above filter. Can someone help me?

Regards,
Maurits