Why is Firefox throwing an error on event.target.id?

Question

JavaScript

Why the new Firefox throws an error on event.target.id
Other browsers work flawlessly.
<a id="3434567" onclick=" load()"> ссылка </a>

function load() {
  var tar = event.target.id;

Answer 1

<a id="3434567" onclick="load"> ссылка </a>

function load(event) {
  var tar = event.target.id;

where can he get the event?

Answer 2

As the great Cat Matroskin bequeathed: in order to trim something unnecessary, you first need to choose something unnecessary. Thus, if you do not choose what is not needed, then you will not have to trim anything. That's why they are regular expressions...
I admit that it's hard to believe, but the ban on learning and writing regular expressions has long been lifted! Today, regular expressions are quite realistic not only to write, but also to check with your own hands, for example here .