Kbin Error when interacting with a page that isn't freshly loaded

Almost any action taken on kbin - whether voting, subscribing, blocking, etc... - if the page you're doing it on was not loaded recently, kbin gives a full page error. So as an example, if I open up a comments page for a thread, if I perform a kbin action on that page right away (e.g. vote, subscribe, block, etc...) it will work. But if I leave the page open for a few minutes before getting to it, then any such action will result in a full page error.   The timing is very reminiscent of when Cloudflare was enabled - because if you interacted with a kbin page that wasn't very recently loaded, you got the Cloudflare page. Since Cloudflare is turned off, I'm not sure why this hidden freshness timer is still causing problems.