When I don't know that Array.prototype.fill() is a thing https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/fill …pic.twitter.com/ccF9V5eNXu
You can add location information to your Tweets, such as your city or precise location, from the web and via third-party applications. You always have the option to delete your Tweet location history. Learn more
Wouldn't the more general fix be that `new Array(n)` should be able to upgrade to packed in certain cases? it might be worth checking whether there are still empty elements if, before any reads happen, we write at least n times to the array?
disclaimer: i know very little about how this stuff works so I'm most likely wrong but i'd love to learn why 
Twitter may be over capacity or experiencing a momentary hiccup. Try again or visit Twitter Status for more information.