Get the source code from Github    -    or the bookmarklet

Result:

https://auto-opkoper-export.be/
Array
(
    [date] => Thu, 30 Jun 2022 22:29:33 GMT
    [server] => Apache/2
    [x-powered-by] => PHP/7.2.34
    [expires] => Wed, 11 Jan 1984 05:00:00 GMT
    [cache-control] => no-cache, must-revalidate, max-age=0
    [upgrade] => h2,h2c
    [connection] => Upgrade
    [vary] => Accept-Encoding,User-Agent
    [content-encoding] => gzip
    [content-length] => 1158
    [content-type] => text/html; charset=UTF-8
)
Array
(
    [url] => https://auto-opkoper-export.be/
    [content_type] => text/html; charset=UTF-8
    [http_code] => 500
    [header_size] => 370
    [request_size] => 124
    [filetime] => -1
    [ssl_verify_result] => 0
    [redirect_count] => 0
    [total_time] => 0.84249
    [namelookup_time] => 0.028483
    [connect_time] => 0.03872
    [pretransfer_time] => 0.07647
    [size_upload] => 0
    [size_download] => 1158
    [speed_download] => 1375
    [speed_upload] => 0
    [download_content_length] => 1158
    [upload_content_length] => -1
    [starttransfer_time] => 0.84223
    [redirect_time] => 0
    [redirect_url] => 
    [primary_ip] => 185.104.29.128
    [certinfo] => Array
        (
        )

    [primary_port] => 443
    [local_ip] => 78.47.42.177
    [local_port] => 51194
    [http_version] => 2
    [protocol] => 2
    [ssl_verifyresult] => 0
    [scheme] => HTTPS
)
<!DOCTYPE html>
<html lang="nl">
<head>
	<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
	<meta name="viewport" content="width=device-width">
		<meta name='robots' content='max-image-preview:large, noindex, follow' />
	<title>WordPress &rsaquo; fout</title>
	<style type="text/css">
		html {
			background: #f1f1f1;
		}
		body {
			background: #fff;
			border: 1px solid #ccd0d4;
			color: #444;
			font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
			margin: 2em auto;
			padding: 1em 2em;
			max-width: 700px;
			-webkit-box-shadow: 0 1px 1px rgba(0, 0, 0, .04);
			box-shadow: 0 1px 1px rgba(0, 0, 0, .04);
		}
		h1 {
			border-bottom: 1px solid #dadada;
			clear: both;
			color: #666;
			font-size: 24px;
			margin: 30px 0 0 0;
			padding: 0;
			padding-bottom: 7px;
		}
		#error-page {
			margin-top: 50px;
		}
		#error-page p,
		#error-page .wp-die-message {
			font-size: 14px;
			line-height: 1.5;
			margin: 25px 0 20px;
		}
		#error-page code {
			font-family: Consolas, Monaco, monospace;
		}
		ul li {
			margin-bottom: 10px;
			font-size: 14px ;
		}
		a {
			color: #0073aa;
		}
		a:hover,
		a:active {
			color: #006799;
		}
		a:focus {
			color: #124964;
			-webkit-box-shadow:
				0 0 0 1px #5b9dd9,
				0 0 2px 1px rgba(30, 140, 190, 0.8);
			box-shadow:
				0 0 0 1px #5b9dd9,
				0 0 2px 1px rgba(30, 140, 190, 0.8);
			outline: none;
		}
		.button {
			background: #f3f5f6;
			border: 1px solid #016087;
			color: #016087;
			display: inline-block;
			text-decoration: none;
			font-size: 13px;
			line-height: 2;
			height: 28px;
			margin: 0;
			padding: 0 10px 1px;
			cursor: pointer;
			-webkit-border-radius: 3px;
			-webkit-appearance: none;
			border-radius: 3px;
			white-space: nowrap;
			-webkit-box-sizing: border-box;
			-moz-box-sizing:    border-box;
			box-sizing:         border-box;

			vertical-align: top;
		}

		.button.button-large {
			line-height: 2.30769231;
			min-height: 32px;
			padding: 0 12px;
		}

		.button:hover,
		.button:focus {
			background: #f1f1f1;
		}

		.button:focus {
			background: #f3f5f6;
			border-color: #007cba;
			-webkit-box-shadow: 0 0 0 1px #007cba;
			box-shadow: 0 0 0 1px #007cba;
			color: #016087;
			outline: 2px solid transparent;
			outline-offset: 0;
		}

		.button:active {
			background: #f3f5f6;
			border-color: #7e8993;
			-webkit-box-shadow: none;
			box-shadow: none;
		}

			</style>
</head>
<body id="error-page">
	<div class="wp-die-message"><p>Er heeft zich een kritieke fout voorgedaan op deze site.</p><p><a href="https://wordpress.org/support/article/faq-troubleshooting/">Meer informatie over probleemoplossing in WordPress.</a></p></div></body>
</html>
	

Fatal error: Uncaught Embed\Exceptions\InvalidUrlException: Invalid url 'https://auto-opkoper-export.be/' (Status code 500) in /var/www/oscarotero.com/www/embed3/src/Embed.php:142 Stack trace: #0 /var/www/oscarotero.com/www/embed3/src/Embed.php(81): Embed\Embed::process() #1 /var/www/oscarotero.com/www/embed3/demo/index.php(216): Embed\Embed::create() #2 {main} thrown in /var/www/oscarotero.com/www/embed3/src/Embed.php on line 142