Playing in a world where slimes appeared regularly but after the December and now the latest update, slimes no longer appear. I've toggled the settings but to no avail. If I use the same seed on a flat world, slimes will appear regularly in the same area that they used to in my infinite world.
Thank you for your report!
However, this issue is a duplicate of MCPE-29401. Please add your vote to that issue, and comment there if you have additional information to add.
Note that the rules for spawning in a flat world are different from those for an infinite world.
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