Astonishing news, apparently oxygen is being produced at the bottom of the sea without use of sunlight.
https://www.nature.com/articles/s41561-024-01480-8
EDIT: This should make it more understandable without wading through miles of data that is largely incomprehensible
https://www.newscientist.com/article/2440460-shock-discovery-reveals-deep-sea-nodules-are-a-source-of-oxygen/