rue]);
    }, "the element should stay connected during the callbacks");

    promise_test(async t => {
        const ce = document.getElementById("ce");
        let reactions = [];
        const element_name = unique_element_name();
        customElements.define(element_name,
            class MockCustomElement extends HTMLElement {
              connectedMoveCallback() { reactions.push("connectedMove"); }
              connectedCallback() { reactions.push("connected"); }
              disconnectedCallback