bug handling new ECMAScript findLastIndex()

[mminea]

Since ECMAScript 2022 arrays have new methods like findLastIndex
I assume their handling in ElementaryJS is simply forwarded.
Every once in a while, findLastIndex returns false when looking for an existing array element (it correctly returns -1 when the element does not exist).
MWE (n=100 is sufficiently large to exhibit every few runs):

test("findLastIndex", () => {
  let a = [];
  for (let i = 0; i < 100; ++i) { a.push(Math.random()); }
  for (let i = 0; i < a.length; ++i) {
    assert(a.findLastIndex((e, _i, _a) => e === a[i]) !== false);
  }
});