download-foto.js

downloadArquivo("./logo.png").then(function(arrayBuffer) {
    var blob = new Blob([arrayBuffer], {
        type: "image/png"
    });
    var img = document.createElement("img");
    img.addEventListener("load", function(e) {
        window.URL.revokeObjectURL(img.src);
    }, false);

    img.src = window.URL.createObjectURL(blob);
    document.body.appendChild(img);
}).catch(function(erro) {
    console.log(erro);
});