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Magento2 join product details in sales order grid as sortable / filterable column

We have added some additional sortable / filterable columns to sales order grid using some basic joins. This would be the relevant code regarding data

app/code/Vendor/Module/etc/di.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <type name="MagentoFrameworkViewElementUiComponentDataProviderCollectionFactory">
        <arguments>
            <argument name="collections" xsi:type="array">
                <item name="sales_order_grid_data_source" xsi:type="string">VendorModuleModelResourceModelOrderGridCollection</item>
            </argument>
        </arguments>
    </type>
    <type name="SinapsisOrderGridModelResourceModelOrderGridCollection">
        <arguments>
            <argument name="mainTable" xsi:type="string">sales_order_grid</argument>
            <argument name="resourceModel" xsi:type="string">MagentoSalesModelResourceModelOrder</argument>
        </arguments>
    </type>
</config>

And then
app/code/Vendor/Module/Model/ResourceModel/Order/Grid/Collection.php

<?php
namespace VendorModuleModelResourceModelOrderGrid;

use MagentoFrameworkDataCollectionDbFetchStrategyInterface as FetchStrategy;
use MagentoFrameworkDataCollectionEntityFactoryInterface as EntityFactory;
use MagentoFrameworkEventManagerInterface as EventManager;
use MagentoSalesModelResourceModelOrder;
use MagentoSalesModelResourceModelOrderGridCollection as OrderGridCollection;
use PsrLogLoggerInterface as Logger;

class Collection extends OrderGridCollection
{

    public function __construct(
        EntityFactory $entityFactory,
        Logger $logger,
        FetchStrategy $fetchStrategy,
        EventManager $eventManager,
        $mainTable = 'sales_order_grid',
        $resourceModel = Order::class
    ) {
        parent::__construct($entityFactory, $logger, $fetchStrategy, $eventManager, $mainTable, $resourceModel);
    }

    protected function _renderFiltersBefore()
    {
        $joinTable = $this->getTable('sales_order');
        $this->getSelect()->joinLeft(
            ['sales_order_table' => $joinTable],
            'main_table.entity_id = sales_order_table.entity_id',
            ['coupon_code']
        );

        $joinTable = $this->getTable('sales_order_address');
        $this->getSelect()->joinLeft(
            ['sales_order_address_table' => $joinTable],
            'sales_order_table.billing_address_id = sales_order_address_table.entity_id',
            ['country_id', 'region', 'city', 'postcode', 'telephone']
        );
        parent::_renderFiltersBefore();
    }
}

Now we want to add a column including some product details, such as product name, sku, etc…

How could we do the join to sales_order_item database table, so we can concatenate all possible results in one single field per order with the products info?