I made a villager farm in survival and i traded up to a bunch of max level farmers so i can trade for emeralds. i then placed down many lecterns to get some Librarians for books. i noticed that around three of the librarians where all ready max level, presumably they had switched profession even after trading with them and they had all of there new trades unlocked
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We're tracking this issue in MCPE-117852, so this ticket is being resolved and linked as a duplicate.
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