package.json

  "dependencies": {
    "preact": "^10.2.1",
    "preact-compat": "^3.19.0"
  }

Portal.jsx

import { Fragment } from "preact";
import { useState, useLayoutEffect } from "preact/hooks";
import { createPortal } from "preact/compat";

export default ({ children, into }) => {
  const [target, setTarget] = useState(null);

  useLayoutEffect(() => {
    setTarget(document.querySelector(into));
  }, []);

  if (target) {
    return createPortal(
      <Fragment>{children}</Fragment>,
      target
    );
  }
}