<!DOCTYPE html>
<html lang="de">
<head>
<meta charset="UTF-8">
<title>URL</title>
<script>
function checkUrl() {
var v = document.urlForm.website.value;
if (v.length !== 0) {
location.href = v;
}
}
</script>
</head>
<body>
<form name="urlForm" onsubmit="checkUrl()">
<input name="website" type="url" required pattern="https?://.+" placeholder="website" value="">
<button type="submit">go</button>
</form>
</body>
</html>
dat funzt