changed to add a specific class for select elements so support is opt in

lib/class-wp-theme-json-gutenberg.php

@@ -601,12 +601,13 @@ class WP_Theme_JSON_Gutenberg {
 		// The block classes are necessary to target older content that won't use the new class names.
 		'caption' => '.wp-element-caption, .wp-block-audio figcaption, .wp-block-embed figcaption, .wp-block-gallery figcaption, .wp-block-image figcaption, .wp-block-table figcaption, .wp-block-video figcaption',
 		'cite'    => 'cite',
-		'select'  => 'select',
+		'select'  => '.wp-element-select',
 	);
 
 	const __EXPERIMENTAL_ELEMENT_CLASS_NAMES = array(
 		'button'  => 'wp-element-button',
 		'caption' => 'wp-element-caption',
+		'select'  => 'wp-element-select',
 	);
 
 	/**

packages/block-editor/src/components/global-styles/use-global-styles-output.js

@@ -42,6 +42,7 @@ import { unlock } from '../../lock-unlock';
 const ELEMENT_CLASS_NAMES = {
 	button: 'wp-element-button',
 	caption: 'wp-element-caption',
+	select: 'wp-element-select',
 };
 
 // List of block support features that can have their related styles

packages/block-editor/src/elements/index.js

@@ -1,6 +1,7 @@
 const ELEMENT_CLASS_NAMES = {
 	button: 'wp-element-button',
 	caption: 'wp-element-caption',
+	select: 'wp-element-select',
 };
 
 export const __experimentalGetElementClassName = ( element ) => {

packages/blocks/src/api/constants.js

@@ -284,6 +284,7 @@ export const __EXPERIMENTAL_ELEMENTS = {
 	caption:
 		'.wp-element-caption, .wp-block-audio figcaption, .wp-block-embed figcaption, .wp-block-gallery figcaption, .wp-block-image figcaption, .wp-block-table figcaption, .wp-block-video figcaption',
 	cite: 'cite',
+	select: '.wp-element-select',
 };
 
 // These paths may have three origins, custom, theme, and default,