Alan-Gomes

const tst = [[1, [2], 3], 4 ,[5]];

const flatten = arr => Array.isArray(arr) ? arr.reduce((ac, val) => ac.concat(flatten(val)), []) : [arr];

console.log(flatten(tst)); // -> [1, 2, 3, 4, 5]

Alan-Gomes

const base64 = await driver.executeScript(`
  var c = document.createElement("canvas");
  var ctx = c.getContext("2d");
  var img = document.getElementById("loadedImage");
  c.width = img.naturalWidth || img.width;
  c.height = img.naturalHeight || img.height;
  ctx.drawImage(img, 0, 0, c.width, c.height);
  return c.toDataURL();
`).replace(/^data:image\/png;base64,/, "");