Yes, a mature hairline. But you are pretty young to have a mature hairline imo. It looks pretty normal and nobody would notice now but honestly I would recommend looking at finasteride to ensure it doesn't get worse.
One way to track a mature hairline is to raise your eyebrows and create forehead wrinkles. The top wrinkle is where your juvenile hairline was. A normal/mature hairline is about on index finger's width above the wrinkle. In the corners It can be 1.5 finger widths. If it's over that it's getting into balding territory.