We (me,
timprov,
moiread, and
alecaustin) have just watched from the window on the 23rd floor as a Carré Rouge march and protest happened in the square outside the hotel, complete with police presence in riot gear off on one of the side streets. It's rather tense.
Please remember that the hotel is connected to the Metro. If the protests continue and the square outside the hotel is a gathering place, Farthing Party guests may well want to be careful about using the Metro to get somewhere farther from the square rather than going out into the middle of it.
moiread notes that tear gas is in common use for these protests, does not disperse quickly--can linger an hour or more--and will not be any more fun to deal with than you think it will. Let's all be careful so that this is a safe, fun weekend for everybody.