- [ ] `z-index: 9999;` seems a little extreme. Use `5000` per; `Liferay.zIndex.MENU`.

https://github.com/liferay/liferay-portal/blob/b08f5ef1982359a76ed4f3127998183621cd384f/portal-web/docroot/html/js/liferay/util.js#L2271