Does the module support multiple value reference fields?

I've partially fixed it with a draft quick patch. The filter contains values now - separate terms as options. But for some reason $view_copy->result contains only one first row, so I don't have values from the second row in the results of the view.

weird, when I add sorting by product variation SKU - I have expected two rows in results of the $view_copy for the filter. Without sorting - 1 row. But in original views results I always get 2 results regardless there is or not sorting.

another one noticed bug. with added selective filters the bulk operations checkboxes have disappeared from the view :((

I've noticed some other bugs e.g. not empty value when twig debug is enabled (so I've moved striping tags earlier and added removing new lines in a value), also noticed errors when $key is not numeric but Entity Storage is selected and I think we need to improve logic when we need to build empty value
$value = $this->t('Empty (@key)', ['@key' => empty($$sub_key) ? json_encode($sub_key) : $sub_key]);

Removed some lines from the patch which are related to another issue.

Fixed option labels.

After testing and debugging other cases, I've reverted almost all changes and just improved one condition as $field->getValue($row); can return FALSE when value of a field is empty. In Drupal\views\Plugin\views\field::getValue():

    if ($field_item_definition->getFieldStorageDefinition()->getCardinality() == 1) {
      return reset($values);
    }

And added one more

        if (is_null($key)) {
          continue;
        }

just in case the code inif (!is_scalar($key) || $key === FALSE) { returns NULL for the $key.

Added small fix to remove new lines from the value.

I appreciate the work here, and I'm contributing additional feature. I also found selective filter wasn't working with entity reference fields when using aggregation. When I use aggregation, the keys we have in the same place here are an array of keys. So I've tried to be the least intrusive and least duplicative as possible. I've kept the work in the original patch, but also included support for arrays of keys when aggregation is turned on and entity reference fields are aggregating with entity ID instead of target ID.