I'm reading a book on the Cold War and there's a bit about the French Strikes in 1947, the ones pictured were from the Renault Factory and each placard has the 10F on it. I'm thinking this is to do with a 10 franc increase in wages, but I'm not sure and for some reason it's really bugging me as to what it means. This is kind of a niche question so not really sure as to if I'll get an answer, but anyone is welcome to take a guess!
I agree with you that it means 'franc'. It makes sense in context (both historically and syntactically): tous unis pour avoir les 10F 'all united to have 10 francs'; 10F, c'est un peu plus de pain '10 francs is a little more bread'.