Add password show/hide eye icon to donpardon.nl

AddPasswordShowHideEyeIcon.js

// ==UserScript==
// @name         Add password show/hide eye icon
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  try to take over the world!
// @author       You
// @match        https://www.donpardon.nl/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=donpardon.nl
// @grant        GM_addStyle
// @grant        GM_getResourceText
// @require      https://cdnjs.cloudflare.com/ajax/libs/jquery/2.2.2/jquery.min.js
// @resource  fa https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css
// ==/UserScript==

/* globals jQuery, $, waitForKeyElements */

// Kudos to: https://codepen.io/Sohail05/pen/yOpeBm

(function() {
    'use strict';

    let faCss = GM_getResourceText('fa')

    const shouldShowPassword = function() {
        const show = window.localStorage.getItem('showPassword')
        if(show == null) {
            return false
        }
        return show == 'true' ? true : false
    }

    console.log(shouldShowPassword())

    // Fixup relative path to fa CSS URL, as we load this via GM_addStyle, the relative path goes to www.donpardon.nl
    // instead of to URL of the fa CSS URL
    faCss = faCss.replaceAll('../fonts', 'https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/fonts')
    GM_addStyle(faCss)

    GM_addStyle(`
      .field-icon {
        margin-left: -25px;
        margin-top: -25px;
        z-index: 2;
      }
    `)

    $('#password').after( '<span toggle="#password" class="fa fa-fw fa-eye field-icon toggle-password"></span>' );
    const shouldShow = shouldShowPassword()
    if(shouldShow) {
        $(".toggle-password").toggleClass("fa-eye fa-eye-slash");
        $('#password').attr("type", "text")
    }

    $(".toggle-password").click(function() {

      $(this).toggleClass("fa-eye fa-eye-slash");
      var input = $($(this).attr("toggle"));
      if (input.attr("type") == "password") {
        input.attr("type", "text");
        window.localStorage.setItem('showPassword', 'true')
        console.log(shouldShowPassword())
      } else {
        input.attr("type", "password");
        window.localStorage.setItem('showPassword', 'false')
        console.log(shouldShowPassword())
      }
    });
})();