The form field and button used in the search field currently appear entirely unstyled:

These styles are largely not customizable via Global Styles or theme.json, which means that every block theme is forced to provide styles via CSS.

To prevent this, we should consider providing some default styles to ensure that this block works nicely right out of the box.

Related: WordPress/twentytwentytwo#11, #34216
Gutenberg version: 11.9.0