Performance

As of 4.0.2 I fixed a bug where countries with utf-8 characters weren't being sorted properly. The Åland Islands would end up getting listed at the very end after Zimbabwe, and not with the A's. Oops!

To resolve that, this script now uses localeCompare for sorting. This works great, but it's quite a bit slower than the previous sorting algorithm.

Recommendation

If you're using the whitelist, blacklist, or priorityOptions props, don't pass in a fresh object as a prop each time. That'll cause an unnecessary and expensive re-sort every time. Instead, memoize the prop instead.

I've documented this issue on those demo pages and added example code so you can see how memoization be be done. See the Priority Options as an illustration.