With the new change of having Master starting at 2100, there is a bug with the rating changes in the contests tab of some people's profiles.
If you look here (sorry I don't know how to insert an image), my latest rating change, where "Became Master" should be, instead says "Became Candidate Master" again.
This is not a huge issue, but I thought I should point it out so it could be fixed by the Codeforces team.
Thanks and have a great day!
EDIT: with some other people, there are some weirder issues with title changes being shown when they are not supposed to be. Ex. linpaws