Converter base64 to inputFile

convert_base64_to_input_file.js

#https://stackoverflow.com/questions/71466930/how-to-get-base64-img-src-and-insert-it-into-input-files 
function dataURLtoFile(dataurl, filename) {
    var arr = dataurl.split(','),
        mime = arr[0].match(/:(.*?);/)[1],
        bstr = atob(arr[1]),
        n = bstr.length,
        u8arr = new Uint8Array(n);

    while (n--) {
        u8arr[n] = bstr.charCodeAt(n);
    }
    return new File([u8arr], filename, {type: mime});
}

function convertBaseToInputFile(base64url, idInputFile, fileNameExtension) {
    var file = dataURLtoFile(base64url, fileNameExtension);
    let container = new DataTransfer();
    container.items.add(file);
    document.querySelector(`#${idInputFile}`).files = container.files;
}



#Usando
convertBaseToInputFile(base64, 'id_inputFile', "namefile.png")

#pegar o file por JS
var newfile = document.querySelector('#id....').files[0];