.settings.php

См. документацию.

<?php
 
return [
    'ui.entity-selector' => [
        'value' => [
            'entities' => [
                [
                    'entityId' => 'highloadblock-element',
                    'provider' => [
                        'moduleId' => 'highloadblock',
                        'className' => '\Bitrix\Highloadblock\Integration\UI\EntitySelector\ElementProvider',
                    ],
                ]
            ],
            'extensions' => ['highloadblock.entity-selector'],
        ],
        'readonly' => true,
    ],
];