google-typing.js

// Intended to be run on https://google.pl
function executeSearchTypingScript() {
  const googleDomain = 'google.pl';

  if (window.location.href.indexOf('google.pl') === -1) {
    throw new Error(`This script should be run on ${googleDomain}`);
  }

  const searchInputField = document.querySelector('[aria-label=Szukaj]');

  const searchText = 'Jiu-jitsu';

  const LETTER_INTERVAL = 200;

  // Question: why do we need to use 'let' here? Why wouldn't 'var' work?
  for (let i = 0; i < searchText.length; i++) {
    setTimeout(function() {
      searchInputField.value = `${searchInputField.value}${searchText[i]}`;
    }, i * LETTER_INTERVAL);
  }

  const form = document.getElementsByTagName('form')[0];

  // Question: why do we need to use 'setTimeout()' here?
  setTimeout(function() {
    form.submit();
  }, searchText.length * LETTER_INTERVAL);
}

executeSearchTypingScript();