The title really says it all. How hot can steam (gaseous form of water) be before it ceases to be steam. I'm assuming that at some point the molecular bonds will give way, though I might of course be wrong.
Edit: I did try and search online but most places seem to talk about how hot you can get steam in engines and similar. I have only found one very strange quora post that seemed to imply temperatures in the range of 100 000K which seemed iffy to me.