View old page data after refreshing

[cate]

I don't know how to better specify it, sorry if that title's confusing.
So, maybe I have a youtube video in a tab, and I go to watch the video 2 hours later, but then the site refreshes and says the video was made private.
Or, I'm browsing 4chan and have some images in multiple tabs. But after refreshing the page, particularly after restarting the computer, the site will give a 404.

I hope it's not a gray area to ask to be able to view content that has been intended to be hidden/deleted, but if it's possible (and if not please explain why), I would love if there was some implementation where when a page is refreshed I can click some "View old page data" button, which would show older "snapshots"

I imagine/hope this would be possible because when you view a 404'd image like on 4chan, your browser still shows you the image which iirc you can still interact/save, and my guess is the browser keeps some temporary data?

[Jon]

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