vanilla JS localStorage persist data on refresh

I'm using vanilla JS and I want to persist data on localStorage when page refreshes:

main.js

localStorage.setItem("language", "ar");

const toEnglish = (e) => {
  if (e.target.closest(".english")) {
    localStorage.setItem("language", "en");
  }
};

document.addEventListener("click", (e) => toEnglish(e));

however, after setting language to en on localStorage, if the page refreshes the value resets to ar, i wonder why it doesn't persist the value like in reactJS ?

It happen because every page load you change language to ar

You need to check is language already set

if (!localStorage.getItem("language")) {
  localStorage.setItem("language", "ar");
}

const toEnglish = (e) => {
  if (e.target.closest(".english")) {
    localStorage.setItem("language", "en");
  }
};

document.addEventListener("click", (e) => toEnglish(e));