Which (js/mockup/pattern) resources are responsible for inline field validation in (easy)form's?

I'm trying to get inline validation working on an public easyform form, so no logged in users. Tested this in plain Plone 5.1.6 with latest easyform release. But it is only working when I'm logged in: when I tab out of an easyform field, @@z3cform_validate_vield is triggered as XHR request to do server side field validation. So I assume it's a resource which is included in the plone-logged-in bundle, which further inspection of the event listener shows:

When I enable development mode and develop javascript in plone-logged-in, I can check in the browser developer tools (Firefox) which events from which code are activated on the input elements. I have found:

  • mockup-patterns-formautofocus
  • mockup-patterns-formunloadevent
  • mockup-patterns-inlinevalidation

So how do I serve these anonmously? I created a new bundle 'frontend-forms', added these three resources, 'merge' the bundle with default and activate the "Does your bundle contain any RequireJS or LESS files?" option. I build the bundle, see that it is now added to the javascript resources and served anonymously

But still no backend validation checks are triggered from an anonymous form.

When I'm logged in and I check the event listeners after adding my new bundle, I do see that the events are now loaded from javascript in my frontend-forms bundle instead of logged-in. So I'm onto something, but am still missing some resources, but which? Or is there another check performed which disables/enables the inline validation? Is it only triggered/activated at all for logged-in users based on body class properties for example?