It's just a casual way of saying friend, used in the same contexts as "bro". Popular with young people, on discord, in games, etc. And yes, also on 4chan. There have been some people trying to retroactively turn it into an acronym for " Far Right Entho Nationalist", to spark a moral panic because they think that's funny. Probably the poster above was credulous enough to fall for that. The overwhelming majority of people who say fren are using it in the simple "bro" sense.
lupusreal|10 months ago
malux85|10 months ago
unknown|10 months ago
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