hx-trigger="change" on a form does not react to input changes "outside" the form

In HTML, it's possible to have form components (buttons, inputs, selects, ...) outside of a form by adding the `form=#myFormId` attribute on them.

```html

Submit

a
b

```
Using HTMX (via hx-boost or hx-get/hx-post) the outside select value is used correctly when making the call ✅ (ex: `/currentPage?text=abc&outside=a`)

But I can't find a way to trigger the form when the outside select value change.

```html

Submit

a
b

```

Example of the behavior: https://plnkr.co/edit/sXNvKYobVl6iD5NQ

A stopgap solution is to add a bit of JS on each out-of-form input: `onchange="this.form.requestSubmit()"` and have `hx-trigger="submit change"`