Or whatever the in lingo is.

My first thought was of the carambars that the French - of a certain age, at least - rave about. Silly naive me. Not only am I not a fan of the things, but neither have I ever touched cannabis in any shape or form, but given the content of the song in question, it has to be referring to 2/3 barres de shit. If I understand the Ouèbbhe correctly, a barre is - or at least was - a 'soap bar'. Not being a user I cannot say for sure, but I get the impression the English term may have changed.

Who'll fess up to knowing about these things?

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Note added at 2 hrs (2024-03-28 00:21:27 GMT)
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I referred to 'the song in question' - easy to find.
The lines "gyrophares des keufs" and "T'as des projets mais tout s'éteint quand la BAC frappe à la porte" (BAC - brigade anti-criminalité - "les policiers de la BAC sont spécialisés dans les interventions à risques en zones urbaines, particulièrement en milieux sensibles (cités ou quartiers prioritaires).")
in particular suggests that something illegal is going on in la cité, like drugs.

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Note added at 9 hrs (2024-03-28 07:10:43 GMT)
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Well, no one has been forthcoming with their drug-related experience, so here's the scale of things. If it is indeed 2/3 barres de shit we're talking about, we're looking at a value of €20/30, indeed a trivial amount for a couple of mates to argue over. But triviality is what it's about, I think, not thousands of euros.

"Ainsi, pour 20 euros de drogue achetée, soit deux barrettes de shit, le client obtient alors, gratuitement, un briquet et un paquet de feuilles à rouler. Pour 50 euros, il bénéficie même d'un paquet de cigarettes. Et pour 10 barres de shit d'une valeur de 10 euros chacunes [sic] achetées, une leur est offerte"
https://www.francesoir.fr/societe-faits-divers/marseille-des...