I spent some time today working on a system to identify similar problems along the lines of https://codeforces.me/blog/entry/113064. For testing, it would be nice to have a list of duplicate (or close to duplicate, "one simple transformation" away, etc.) problems on Codeforces. The only pair I am currently aware of is (1793F - Rebrending, 765F - Souvenirs), so any others would help. Thanks!
EDIT: Just to be clear, I'm not interested only in strict duplicates, but also problems that share some important subtask, observation, or pairs in which one problem is a generalization of the other. And not asking for anyone to put any work into this, just thought some people might have pairs that immediately come to mind when they read this :)