When using Lingering Potions the particle effects don't disappear at all, even when reloading the world. I've also tried killing them with the /kill command but it says there are't any valid entities to kill half the time. They also don't actually give you the effect they are assigned in any given mode (0-2).
There is another thing though. These annoying white outlines surround some of the blocks placed by players.
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However, this issue has been closed as a Duplicate of *Lingering Potions *.
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