This is a bug that seems to happen entirely at random, but AOE clouds don't seem to spread properly, and instead stay stuck and isolated in a small point, and do not give potion effects when walked through. This also affects the End Acid.
MCPE-44413
Lingering Potions not functional
Resolved
Duplicate
0
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-39595.
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