May also ignore biome, slime will spawn in any biome. (I am not sure whether or not only spawns on slime chunks), but slime will spawn on the surface even if it's not in the swamp.
duplicates MC-136051
This also happens in my worlds.
And all of these occur at the edge of the chunks.
It seems that it still affects 1.13.
Spirited_Away_
May also ignore biome, slime will spawn in any biome. (I am not sure whether or not only spawns on slime chunks), but slime will spawn on the surface even if it's not in the swamp.
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