I had just started a survival world when I was looking for a forest. I came across some ponds in a birch biome where trees were floating. I have shown where I found it in the seed -5792391265540249922.

Video Proof: 

https://drive.google.com/file/d/1AYFl8mphNWTg4XG_sdWVB2FvgOsEWa5L/view?usp=sharing