How to check high scores in lichess?

Like chess.com you can check a peak rating for a user, how to do this on lichess, if not I think it should be available.

All other chess websites have it.

Profile has a graph with that data.

#2 Thats not entirely true.
If you play one day and reach say 2200 at one point, then you lose some games after. Your graph will show what you ended the day on, not your highest peak.