SVGAnimationElement: beginEvent event

addEventListener("beginEvent", (event) => { })

onbegin = (event) => { }

<svg xmlns="http://www.w3.org/2000/svg" width="300px" height="100px">
  <title>SVG SMIL Animate with Path</title>
  <circle cx="0" cy="50" r="50" fill="blue" stroke="black" stroke-width="1">
    <animateMotion path="M 0 0 H 300 Z" dur="5s" repeatCount="indefinite" />
  </circle>
</svg>

<hr />

<ul></ul>

ul {
  height: 100px;
  border: 1px solid #dddddd;
  overflow-y: scroll;
  padding: 10px 30px;
}

let svgElem = document.querySelector("svg");
let animateElem = document.querySelector("animateMotion");
let list = document.querySelector("ul");

animateElem.addEventListener("beginEvent", () => {
  let listItem = document.createElement("li");
  listItem.textContent = "beginEvent fired";
  list.appendChild(listItem);
});

animateElem.addEventListener("repeatEvent", (e) => {
  let listItem = document.createElement("li");
  let msg = "repeatEvent fired";
  if (e.detail) {
    msg += `; repeat number: ${e.detail}`;
  }
  listItem.textContent = msg;
  list.appendChild(listItem);
});

animateElem.onbegin = () => {
  console.log("beginEvent fired");
};