While the Mangrove Swamp has been added, there's no frogs spawning in the biome at all.
How to reproduce
1. Create a 126.96.36.199/21 with this seed: 3100535380006071676
2. Teleport youself to the following position, XYZ: -1400, 70, 2700
While you'll find a lot of bees, there will be no frogs spawning at all.