How to deal with Slack Warriors

Co workers and colleagues who seem OK to talk and discuss in person turn passive aggressive and boss around on Slack channels. They use terms like “As discussed multiple times” , “despite mentioning” etc etc and when you talk to them in person everything seems fine and you start wondering why do they push others down in the first place? Is to to show seniors/managers that there’re more superior? How do you deal with such people? Any tips ?