browser crash occurred when uploading data to the server

upload more data, including 2 to 3 base64

related codes

  <Upload :show-upload-list="true" :headers="{"token":user}" 
  accept="application/pdf"
  multiple
  action="//jsonplaceholder.typicode.com/posts/"
  :on-success="handleSuccess" 
  :before-upload="handleBeforeUpload">
  <Button type="ghost" icon="ios-cloud-upload-outline"></Button>
  </Upload>
          
handleBeforeUpload(file) {
  var reader = new FileReader();
  reader.readAsDataURL(file);

  reader.onloadend = () => {
    this.upList.push(reader.result);
    this.$set(this.list, "value", this.upList);

    console.log(this.list);
  };

  return false;
},

the data is saved successfully and is not very slow

errors are as follows: