During the the game it sometimes hangs with message on server console:

...
> ["GAMEMSG","A3J8RQ=="]
< ["GAMEMSG","A3J8RQ=="]
> ["GAMEMSG","A1J80g=="]
< ["GAMEMSG","A1J80g=="]
> ["GAMEMSG","A059Ow=="]
< ["GAMEMSG","A059Ow=="]
> ["ROUNDFINISHED"]

But everybody is still connected and are able to chat. It happens during a change of turn, for example when a box with healt is going to fall down but it hangs in the air and next turn never starts. It is true for both two and three players game.