Lump over roosters eye

[Jessmp7]

Does anyone know what this lump could be above our roosters eye? He’s acting normally and doesn’t seem sick but I’m worried if it’s an infection it’ll spread. Any tips would be helpful!

 

[Eggcessive]

Is the area soft like air under the skin or firm? A tumor or injury to an air sac could cause that type of swelling. Has there been any others with a respiratory infection or disease, or have any new birds been added to the flock in recent weeks?