[css-forms-1] Does the Basic Appearance UA Stylesheet define intrinsic sizing?

[gitspeaks]

With the release of CSS Form Control Styling Level 1, does Appendix A ("Basic Appearance User Agent Stylesheet") define how intrinsic sizing (especially width: auto / height: auto) should behave for form controls?

Example from the appendix:

select {
  /* Base appearance: select always sizes based on its contents. */
  field-sizing: content !important;
}

Per the spec, field-sizing: content tells the UA to size based on content and ignore any default preferred size defined by the host language.

Does this mean width: auto for <select> effectively behaves like max-content or fit-content?

Are these UA styles meant to align with, or establish, a new standard for automatic sizing of form controls?