How can I stop secondhand marijuana smoke from my neighbor’s unit?

this was never an issue before where i lived but the unit beside me had been vacant for a while after long time tenant moved out and this new family just moved in.

my unit is actually on the second floor and appears someone from there unit opens the back door late at night and smokes marijuana outside , i usually leave my window open especially being the summer to keep room cool but smoke has been coming in and leaving a scent and such , i don't smoke myself and my unit is full of books and clothes so don't really want it to start smelling weird

Updates
8 d
caught it in time noticed a smell emerging and closed window before it got too bad , he seems to go out there late like after 10pm , perhaps one of those who thinks he needs to smoke to go to bed maybe?
How can I stop secondhand marijuana smoke from my neighbor’s unit?
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