I use the Wayback Machine extension (https://chrome.google.com/webstore/detail/wayback-machine/fpnmgdkabkmnadcjpehmlllkndpkmiak https://chrome.google.com/websto

I use the Wayback Machine extension (https://chrome.google.com/webstore/detail/wayback-machine/fpnmgdkabkmnadcjpehmlllkndpkmiak https://chrome.google.com/webstore/detail/wayback-machine/fp...) - if a webpage no longer exists, the Wayback Machine will give me an archived copy of it.