How does the world appear to a person who has strabismus?

Depends: If the strabismus is in childhood, then usually the vision in one eye is supressed and everything looks normal to this child. Measurement will show the reduced vision in one eye which prevents doubling. If the strabismus is acquired in an adult, then the world is doubled and treatment is mandatory for proper functioning. Discuss this will your ophthalmologist.

Duration matters: That depends on how long it’s been part of the person’a experience. If it’s since birth, the brain has likely adjusted and the person sees relatively normally. But, if it’s new, the person will see double any time the eyes aren’t properly aligned.