I don't know about Russia but there seem to be loads of cases of people being arrested (or detained or harrassed by police) for holding up a blank piece of paper, including one case in Cornwall: https://netpol.org/2023/02/10/cornish-protester-assaulted-an...
In Singapore someone was charged for holding up a piece of cardboard with a smiley face drawn on it: https://www.economist.com/asia/2020/11/26/public-order-in-si...