How do you cope with working with unprofessional people?

With boundaries and by setting a better example.

I’ve learned to brush most things off...

There are so many people in the world, the concept of professionalism isn’t as universal as we think.

I suppose it depends on what level of unprofessional-izm they are on.

I usually just stop what I'm doing and give them a long hard stare. They usually avoid me after that.

I retired.

I pretend they're not there.

direct professional conversation

I do accept that and the Boss, I fire them.😜

Run to the boss and get them in trouble

I would be one of those people jk um I just ignore them if I can 😁

Do they get their job done well and on time? If so, there's no problem from me.
They could wear pajamas for all I care.