Function for random base 58 string generation (good for password redefinitions)

random-base58.js

function randomBase58(digits) {
  digits = digits || 0
  var base58 = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'.split('')
  var result = ''
  var char
  while (result.length < digits) {
  	char = base58[Math.random() * 57 >> 0]
  	if (result.indexOf(char) === -1) result += char // avoid repetitions
  }
  return result
}

Updated a bit as IPFS will break if the pattern Qm exists in the result.

function randomBase58(digits = 0) {
  const base58 = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'.split('')

  let result = ''
  let char

  while (result.length < digits) {
    char = base58[Math.random() * 57 >> 0]

    if (result.indexOf(char) === -1) result += char
    if (result.indexOf('Qm') > -1) result = ''
  }

  return result
}