On my last session one of my players became invisible with the whole team, but the enemy could, and did, cast see invisibility. Then my player argued that, in resulting combat, they still had advantage on attack rolls, and there was disadvantage on attack rolls aginst them, because seeing them does not remove invisibility from them, so that still counts. I told him that makes the spell see invisibility, well, useless and ruled against it. He got mad. So I come here with this question. Invisible condition and see invisibility for context:
Invisible
- An invisible creature is impossible to see without the aid of magic or a Special sense. For the Purpose of Hiding, the creature is heavily obscured. The creature’s Location can be detected by any noise it makes or any tracks it leaves.
- Attack rolls against the creature have disadvantage, and the creature’s Attack rolls have advantage.
See Invisibility
[...]
For the duration, you see invisible creatures and objects as if they were visible, and you can see into the Ethereal Plane. Ethereal creatures and objects appear ghostly and translucent.