How to document.getElementById with more than one ID?

Question

how can I add more than one ID in the following code?

function myFunction() {
    var popup = document.getElementById("myPopup");
    popup.classList.toggle("show");
}

I have tried tried it with querySelectorAll but then no popup shows?

 function myFunction() {
    var popup = document.querySelectorAll("#myPopup, #myPopup2");
    popup.classList.toggle("show");
}

Answer 1

querySelectorAll returns a NodeList which must be traversed through to access each element:

document
  .querySelectorAll('#myPopup, #myPopup2')
  .forEach(function(element){
    element.classList.toggle("show");
  })