Faceting error on string list

Hey!

We’re getting a strange error when passing a string array into a refinement list widget. We configured it in exactly the same way as our (functioning) non-array fields. The widget even correctly lists the possible options. However, when we hit one of the checkmarks, we get the following error:

instantsearch.js@^4.3.1:formatted:7758 Uncaught (in promise) TypeError: Cannot read property 'toString' of undefined
 at instantsearch.js@^4.3.1:formatted:7758
    at instantsearch.js@^4.3.1:formatted:7759
    at Array.map (<anonymous>)
    at dn.Dr [as constructor] (instantsearch.js@^4.3.1:formatted:7751)
    at dn.Fn [as render] (instantsearch.js@^4.3.1:formatted:5073)
    at Pn (instantsearch.js@^4.3.1:formatted:4985)
    at instantsearch.js@^4.3.1:formatted:4850
    at bn (instantsearch.js@^4.3.1:formatted:4894)
    at bn (instantsearch.js@^4.3.1:formatted:4892)
    at yn (instantsearch.js@^4.3.1:formatted:4836)

We’re importing the API with:

<script src="[https://cdn.jsdelivr.net/npm/instantsearch.js@^4.3.1](https://cdn.jsdelivr.net/npm/instantsearch.js@%5E4.3.1)"></script>
<script src="https://cdn.jsdelivr.net/npm/algoliasearch@4/dist/algoliasearch.umd.js"></script>

Hi @sam5,

To help us see exactly what might be going wrong, do you mind reproducing the error by creating a similar widget in a code sandbox environment?

You can use this boilerplate instantsearch.js one as a base: https://codesandbox.io/s/github/algolia/create-instantsearch-app/tree/templates/instantsearch.js

Thanks a lot!