Test plugin to ensure that a stylesheet enqueued in the footer will get printed and moved to the head in WordPress 6.9. See https://wordpress.org/support/topic/wordpress-6-9-broke-site-layout-crewbloom/page/3/#post-18758001

README.md

Run on WordPress Playground

blueprint.json

{
	"$schema": "https://playground.wordpress.net/blueprint-schema.json",
	"meta": {
		"title": "Try enqueueing a stylesheet at wp_footer",
		"author": "westonruter",
		"categories": [ "plugins" ]
	},
	"landingPage": "/",
	"preferredVersions": {
		"php": "8.3",
		"wp": "6.9"
	},
	"steps": [
		{
			"step": "installTheme",
			"themeData": {
				"resource": "wordpress.org/themes",
				"slug": "twentytwentyone"
			},
			"options": {
				"activate": true
			}
		},
		{
			"step": "installPlugin",
			"pluginData": {
				"resource": "url",
				"url": "https://gist.github.com/westonruter/30db2216eef07600cb1762ee8be67f18/archive/HEAD.zip"
			},
			"options": {
				"activate": true,
				"targetFolderName": "enqueue-styles-at-wp-footer"
			}
		}
	]
}

enqueue-styles-at-wp-footer.php

<?php
/**
 * Plugin Name: Enqueue Stylesheet at wp_footer
 * Plugin URI: https://wordpress.org/support/topic/wordpress-6-9-broke-site-layout-crewbloom/page/3/#post-18758001
 * Description: Attempt to enqueue a stylesheet at <code>wp_footer</code> to test whether it is hoisted to the <code>HEAD</code> in a classic theme.
 * Requires at least: 6.9
 * Version: 1.0
 * Author: Weston Ruter
 * Author URI: https://weston.ruter.net/
 * License: GPLv2 or later
 * License URI: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * Gist Plugin URI: https://gist.github.com/westonruter/30db2216eef07600cb1762ee8be67f18
 * Primary Branch: main
 */

add_action(
	'wp_footer',
	static function () {
		if ( is_front_page() ) {
			wp_enqueue_style('enqueued-at-wp-footer', plugins_url( 'enqueued-at-wp-footer.css', __FILE__ ) );
		}
	}
);

enqueued-at-wp-footer.css

body:after {
	content: "Stylesheet successfully enqueued at wp_footer!";
	background: lime;
	padding: 1em;
	position: fixed;
	bottom: 0;
	right: 0;
}

The installPlugin step might be better as:

		{
			"step": "installPlugin",
			"pluginData": {
				"resource": "zip",
				"inner": {
					"resource": "git:directory",
					"url": "https://gist.github.com/westonruter/30db2216eef07600cb1762ee8be67f18",
					"ref": "main"
				}
			},
			"options": {
				"activate": true,
				"targetFolderName": "enqueue-styles-at-wp-footer"
			}
		}