objeto de archivo de descarga js
<input type="file" id="uploader"/>
<script>
// Download an image from a File() Object:
uploader.addEventListener("change", e =>{
const file = e.target.files[0];
const blob = new Blob( [file], { type: file.type } );
const elem = window.document.createElement('a');
elem.href = window.URL.createObjectURL(blob);
elem.download = file.name;
document.body.appendChild(elem);
elem.click();
document.body.removeChild(elem);
})
</script>
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