Вызов функции после закрытия окна

let log=document.querySelector('div'), 
res 
window.addEventListener('blur',()=>{ 
  res=false 
  log.textContent='User choosing some file...' 
}) 
document.querySelector('#uploadfile').addEventListener('change',()=>{ 
  res=true 
  log.textContent='File was chosen!' 
}) 
window.addEventListener('focus',()=>{ 
  if(res) return 
  log.textContent='Got cancelation :(' 
})

<input type="file" id="uploadfile" /> 
<div></div>