I hate to weigh in here, but nothing is "perfectly safe"! This kind of absolute language seems to create distrust when people discover it's not quite true.

At this stage, the safety is fairly quantifiable, too: https://www.publichealthontario.ca/en/health-topics/immuniza... has a weekly adverse effects report which breaks down myocarditis/pericarditis by sex and age, per million population (the most common dangerous side effect for mRNA vaccines).