POTUS refusal to obey orders from the Supreme Court, illegal deportation of a US resident, inciting an attack on Congress, banning the right to protest, making free speech illegal by ordering universities to stop using numerous words...

It's not a natural reaction for most Canadians either and many are angered at this booing but it is one of the only ways we can demonstrate how pissed off we are. The great majority of Canadians know that it's not all Americans who are MAGA followers but emotions are hard to control.