Custom columns on custom taxonomy terms in admin

manage_{taxonomy-slug}_custom_column.php

<?php
/*
 * Custom columns on edit terms screens i admin
 * */
add_filter( 'manage_edit-{taxonomy-slug}_columns', 'hip_{taxonomy-slug}_columns_head' );
add_filter( 'manage_{taxonomy-slug}_custom_column', 'hip_{taxonomy-slug}_columns_content_taxonomy', 10, 3 );
function hip_{taxonomy-slug}_columns_head( $columns ) {

    unset( $columns['posts'] ); // unset the posts column
    unset( $columns['slug'] ); // unset the slug column

    $columns['new_column']  = __( 'New column heading', 'textdomain' );

    return $columns;
}
function hip_{taxonomy-slug}_columns_content_taxonomy( $deprecated, $column_name, $term_id ) {

    if ( $column_name == 'new_column' ) {
      $foobar = 'Foobar!';
      echo $foobar;
    }

    return $columns;
}