The issue is that villagers in 18w09a don't get willing to breed. They are not getting the green particles after trades and in any test set-up I did they wouldn't breed.
I've tested a few identical set-ups in both release and 18w09a and what works in release won't work in the snapshot.
I couldn't find anything anywhere that villagers changed for 1.13 content so I assume it's a bug.
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Comments 3
Duplicate of MC-123055, unless you don't get the purple particles either.
Do you get green particles the first time you do a trade?