I wonder how hard would it be to build a extension for a browser that checks the doi of the paper youre looking at on scihub against the live version, to see if there’s a retraction/update to the paper, and list the date of the changes. I assume that information wouldn’t be behind a paywall.

The reason for it being via an extension is to reduce load on sci hub, and for the lookup requests to be decentralised and live for the relevant paper