comments_block_form_defaults() │ WP 6.1.0

Use the button block classes for the form-submit button.

No Hooks.

Returns

Array. Returns the modified fields.

Usage

comments_block_form_defaults( $fields );
$fields(array) (required)
The default comment form arguments.

Changelog

Since 6.1.0 Introduced.

comments_block_form_defaults() code WP 6.9.1

wp-includes/blocks/comments.php 
function comments_block_form_defaults( $fields ) {
	if ( wp_is_block_theme() ) {
		$fields['submit_button'] = '<input name="%1$s" type="submit" id="%2$s" class="%3$s wp-block-button__link ' . wp_theme_get_element_class_name( 'button' ) . '" value="%4$s" />';
		$fields['submit_field']  = '<p class="form-submit wp-block-button">%1$s %2$s</p>';
	}

	return $fields;
}