I am trying to get a website form to map the data captured by its fields to a model.

I have a custom model x_new_title​​ and have ensured that Allowed to use in forms​​ is enabled in Database Structure > Models​​.

In the website builder I have a form where the Action​​ is set to Create New Title​​ i.e. a record in the custom model.

When I add a Field​​ to the form and try to set the Type​​ to an existing field from the x_new_title​​ model, I get UncaughtPromiseError > TypeError​​ (full error below).

This seems to happen even when selecting pre-existing core models for the form's action. Am I missing something about how this is intended to work?

We are evaluating Odoo for our business. If we can't resolve this issue we'll have to use another service.

Odoo Client Error

UncaughtPromiseError > TypeError

Uncaught Promise > Cannot read properties of undefined (reading 'map')

Occured on expensive-hobby.odoo.com on 2025-08-19 06:43:58 GMT

TypeError: Cannot read properties of undefined (reading 'map')
    at FormOptionPlugin.replaceField (https://expensive-hobby.odoo.com/web/assets/1/841915c/website.website_builder_assets.min.js:2166:35)
    at ExistingFieldAction.apply (https://expensive-hobby.odoo.com/web/assets/1/841915c/website.website_builder_assets.min.js:2217:154)
    at callApply (https://expensive-hobby.odoo.com/web/assets/1/841915c/website.website_builder_assets.min.js:925:599)
    at async commit (https://expensive-hobby.odoo.com/web/assets/1/eeac506/web.assets_web.min.js:13314:137)
    at async applyOperation (https://expensive-hobby.odoo.com/web/assets/1/841915c/website.website_builder_assets.min.js:782:1)
    at async https://expensive-hobby.odoo.com/web/assets/1/841915c/website.website_builder_assets.min.js:782:30