di.xml

<?xml version="1.0"?>
<!--
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
-->
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <virtualType name="Magento\Catalog\Ui\DataProvider\Product\Form\Modifier\Pool">
        <arguments>
            <argument name="modifiers" xsi:type="array">
                <item name="config" xsi:type="array">
                    <item name="class" xsi:type="string">Magento\InventoryLowQuantityNotificationAdminUi\Ui\DataProvider\Product\Form\Modifier\SourceItemConfiguration</item>
                    <item name="sortOrder" xsi:type="number">300</item>
                </item>
            </argument>
        </arguments>
    </virtualType>
    <type name="Magento\Framework\App\Rss\RssManagerInterface">
        <arguments>
            <argument name="dataProviders" xsi:type="array">
                <item name="notifystock" xsi:type="string">Magento\InventoryLowQuantityNotificationAdminUi\Block\Adminhtml\Rss\NotifyStock</item>
            </argument>
        </arguments>
    </type>
</config>