[6chars]

Maybe an enhancement would be to have it look at the edit history and use the most recent URL that has remained on the page for at least X hours/days

[l33t233372]

One challenge with this approach can be seen by considering a scihub takedown followed immediately by a correction to a new TLD. The new(and suddenly correct) address would be changed to an incorrect old address.

[8n4vidtmkvmk]

pop up a warning instead to say there's been churn and let the user pick?

[ranger_danger]

That would take way too long.