Swiggy_bulk_downloader.js

function download(url, filename) {
    fetch(url).then(function(t) {
        return t.blob().then((b)=>{
            var a = document.createElement("a");
            a.href = URL.createObjectURL(b);
            a.setAttribute("download", filename);
            a.click();
        }
        );
    });
}

async function task(i) {
    await timer(1000);
    console.log(`Task ${i} done!`);
  }
  
async function main() {
   for(let i = 0; i <= 960; i++) { 
       let r = /\d+/;
       let textContent = document.querySelectorAll('._2uT6l')[i].innerText; 
       swiggyID = textContent.match(r);
       download("https://www.swiggy.com/invoice/download/"+swiggyID);
       await task(i);
    }
}
  
main();

function timer(ms) { return new Promise(res => setTimeout(res, ms)); }

1. Log in to swiggy.com
2. Run the above script in chrome console.