I believe this happened on the Biosphere level, doing the Holo-ween quest. My char died (as is normal) and I typed "Owie" and it went into public chat, but my keyboard wouldn't drop down. I also couldn't type anything further after that. I went ahead and respawned at the start, but the keyboard was still there, no way to get it to drop or to even explain to the group what was going on. I popped out of the game and back in--keyboard still up. I couldn't log off since the log off button was covered by the keyboard (if I'd been half-smart, I could've split the keyboard and likely reached it. I wasn't.). I did a forced close and a complete shut down and things seem to be back to normal again.

It may be that the forced close will fix whatever little glitch it was, but if not, at least it's reported.