form.file.value = "";
    form.msg.focus();
  });
  /* Handle image paste from clipboard. TODO: confirm that we only
     paste images here (silently ignore non-image data), or change the
     related code to support non-image pasting/posting. */
  document.onpaste = function(event){
    if(form.msg === event.target) return;
    const items = event.clipboardData.items;
    ImagePasteState.blob = items[0].getAsFile();
    const reader = new FileReader();
    reader.onload = function(event){
      ImagePasteState.imgTag.setAttribute('src', event.target.result);
    };
    reader.readAsDataURL(ImagePasteState.blob);

  }
  async function poll(){
    if(poll.running) return;
    poll.running = true;
    fetch("chat-poll/" + mxMsg)
    .then(x=>x.json())
    .then(y=>newcontent(y))
    .catch(e=>console.error(e))
    .finally(()=>poll.running=false)
  }
  poll();
  setInterval(poll, 1000);
})();