When I finished the map I backed out the map selection screen, clicked on that play, went back out and it had duplicated. I re-clicked the replay, backed out, and it duplicated a third time. This is the 2nd time it has happened to me. You can click on it as many times as you want and it keeps duplicating.
https://osu.ppy.sh/ss/7617129
https://osu.ppy.sh/ss/7617247
osu! version: 20170222.3 (latest)
https://osu.ppy.sh/ss/7617129
https://osu.ppy.sh/ss/7617247
osu! version: 20170222.3 (latest)