I was chasing the paper-trail of this recent question - https://photo.stackexchange.com/questions/85243/a-sharp-lens-for-canon
Being new here I like to follow the breadcrumbs often to see what has been well-answered before.
The breadcrumbs, however, have gone stale...
Why are my photos not crisp? may have been a great resource had later followers been able to find the 'dog with sunglasses'. Unfortunately the OP's link is now a 404.
There have been comments regarding its revival, but so far with no result.
Even if we can't preserve the entirety of someone's Flikr stream for posterity [not that we'd really want to] it would be very nice to be able to see even a reduced quality i.stack.imgur version of it long after the initial Q/A has dropped off the active posts list.
If high rep users spot off-site links with potential for link-rot, would we think it useful to copy over to i.stack for posterity, even at low-res?