Graphql - startswith filter

<%- if @topic_view.topic.tags.present? %>
<%= t 'js.tagging.tags' %>: <%- @topic_view.topic.tags.each do |t| %> <%= t %> <%- end %>
<% end %>

Silverstripe Version:
ss4.4.4
Question:
Has anyone got startswith filter to work? I followed SS/Graphql’s documentation, but got this slapped on my face

```
{
  "errors": [
    {
      "message": "Filter startswith not found",
......
```

I see “startswith” is defined here silverstripe-graphql/filters.yml at 3 · silverstripe/silverstripe-graphql · GitHub, and I follow what GitHub - silverstripe/silverstripe-graphql: Serves SilverStripe data as GraphQL representations says - but no dice.