Well, when I try to write a tweet (specifically opening the compose tweet window on Twitter) the keyboard appears and one second later disappears, it tooks like 30-45 seconds to reappear with the "Loading predictions" message and after a while it works normally, so it makes me think that Twitter somehow force closes the keyboard but the force closing notification never shows up.
So, what do you think? It's a Twitter app related problem? SwiftKey is reacting bad to Twitter? Or is something else?
Btw I'm running 6.0 stock on my Moto X Force.