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It's established in Sage Advice that the fighter class feature Fighting Style: Archery only applies to weapons in the "Ranged Weapons" table, not to thrown weapons. Jeremy Crawford says:
That's correct. A melee weapon with the thrown property is still a melee weapon when you throw it.
Does this mean that thrown weapons get the benefit of dueling? (That is, is "When you are wielding a melee weapon in one hand and no other weapons, you gain a +2 bonus to damage rolls with that weapon.")
That seems like a kind of ... odd result.