Disney says
Angus Beef Patty on an Allergy-friendly Bun with lettuce served with choice of Mixed Fruit or French Fries.
Friendliest.app says
The hamburger can be served on an allergy-friendly bun that is free of gluten/wheat, dairy/milk, fish, shellfish, peanuts, tree nuts and soy.

French fries are fried in a dedicated fryer to reduce cross-contamination.

This meal contains eggs (bun) and soy (french fries). It can be made soy-friendly by selecting the mixed fruit instead of french fries.

If ordered with the house burger sauce, this meal may also contain wheat/gluten, milk/dairy eggs and soy.