My flock seems to have something going on with reoccurring facial swelling. It is usually the brow or corner of the mouth, sometimes both. It has never gotten to the point of an eye swelling shut or beak swelling open, and there has never been any puss or discharge from either the swellings themselves or the eyes and/or nostrils. Their behavior seems unaffected and they have all eventually cleared up on their own. It’s just happened to enough of them now that I’m wondering what could be causing this and if it is a problem.