Chat heads

This is a big one for me as someone who frequently multitasks. As far as I know, Facebook Messenger is the only app out there currently supporting a chat heads feature, which I find very useful. For one or two people I've convinced to try Riot, the lack of them was a bit of a deal breaker, or at least a major downside. I think this feature being an option (perhaps even disabled by default as they can be annoying), would make Riot a lot more appealing to some groups and would make it more alike to other popular chat apps (read: Messenger) making transitions easier.