amex.js

const fun = `
(async () => {
  const sleep = (timeout) => new Promise((resolve) => setTimeout(resolve, timeout));
  const btns = [...document.getElementsByClassName("btn")].filter( it => it.title === "Add to Card");
  for (let i = 0; i < btns.length; i++) {
    btns[i].click();
    await sleep(1000);
  }
})()
`;

console.log(`javascript: {${fun.replace(/\n+/g, '')}}; void (0);`)