The azalea trees that mark lush caves can spawn on icebergs. I'm not sure its a bug, but it looks really weird.

I was messing around in the most recent snapshot as of this time, 21w41a, and I happened upon one of the azalea trees that mark lush caves growing out of an iceberg. This seems odd to me so I figured that mojang might want to make it so that the dirt block and tree cannont grow out of the ice varients.