[joshpearson]

Do you know of any sites that do it correctly?

I've created various pages that sorta unrenders content, but all of them break the browser's find.

[minitech]

I don’t, sorry. If regular pagination is at all an option for you, that’s a safe and user-friendly choice.

[thinkloop]

This site does it: http://www.goodlist.co/

If you inspect you will notice that previous invisible items are represented by a single large div who's height increases as more items are scrolled out of view.

[minitech]

> previous invisible items are represented by a single large div

… breaking the browser’s Find. Also, things jump around the page as you scroll down. That site does it decidedly wrong.