Title is self-explanatory, happens with any type of splash or lingering potion. You only get water, no effects.
Related issues
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Confirmed.

Relates to MC-85835.
Title is self-explanatory, happens with any type of splash or lingering potion. You only get water, no effects.
Confirmed.
Relates to MC-85835.
_zombiehunter
(Unassigned)
Unconfirmed
Minecraft 15w46a
Retrieved
Confirmed. Happens with all default and custom potions; the item data from the inventory potion is not stored on the ThrownPotion (defaulting to splash_potion with no effects, as well as a "ThrownPotion entity # has no item?!" error in log).