Adding an event listener to an element that doesn’t exist yet in vanilla javascript

Use the target property in the event object to get the clicked element. Then, manually test for type/attributes/ids

document.addEventListener( "click", someListener );

function someListener(event){
    var element = event.target;
    if(element.tagName == 'A' && element.classList.contains("someBtn")){
        console.log("hi");
    }
}