Show User ID

// 1. Add the ID column after the Username column

function add_user_id_column($columns) {

    $new_columns = array();

    foreach ($columns as $key => $value) {

        $new_columns[$key] = $value;

        // Insert 'user_id' column right after 'username'

        if ($key === 'username') {

            $new_columns['user_id'] = 'ID';

        }

    }

    return $new_columns;

}

add_filter('manage_users_columns', 'add_user_id_column');

// 2. Populate the ID column with the actual user ID

function show_user_id_column_content($value, $column_name, $user_id) {

    if ($column_name === 'user_id') {

        return $user_id;

    }

    return $value;

}

add_filter('manage_users_custom_column', 'show_user_id_column_content', 10, 3);