I was looking around in the Minecraft Beta (Xbox Insider Program Beta) and I was exploring the Caves and Cliffs update. I entered a ravine and the was lava inside of water without interacting with it (making cobblestone or obsidian). I don't know how common this bug is and I don't know if it is happening on other versions but I just thought I would let you know. I know it isn't very game breaking but it is a bug.