Variants not working with XHR Turbo Stream responses

[HashNotAdam]

Steps to reproduce

1. Create a component that includes both a standard template and a variant.
2. Load a page showing the component
3. Submit a form
4. In the receiving controller, set the variant, then respond using a turbo stream

Expected behavior

The variant version of the component should be shown

Actual behavior

The default template is rendered

Example repo

This repo includes the recommended HomeController. The root page has 2 buttons, "Request Turbo Drive response" and "Request Turbo Stream response". Both buttons submit a form HomeController#create and in both cases the action sets request.variant = :compact.

The difference, however, is that the Turbo Drive version returns the compact variant, while the Turbo Streams version returns the default template. The page also displays the value of request.variant as well as the name of the variant that was loaded.

First page load

Response from Turbo Drive

Response from Turbo Stream

System configuration

Rails version: 7.1.3.2

Ruby version: 3.2.2

Gem version: 3.11.0