An ES6 function to compute the mode(s) of an array. All modes found will return

es6-mode.js

// Credits go to @Anjuna5 for original code: https://stackoverflow.com/a/39838257/9779148

const mode = arr => [...new Set(arr)]
  .map(value => [value, arr.filter((v) => v === value).length])
  .sort((a,b) => b[1] - a[1])
  .filter((v, i, a) => v[1] === a[0][1])
  .map(v => v[0]);