This bug is actually pretty simple to be found, you just need to make an advancement with a loot reward and try to obtain it with a full inventory, the loot will just vanish and never be given.
Expected behaviour: Summon the loot at the player’s location.
Actual behaviour: The loot vanishes.
Comments 2
Hi!
Thank you for your report!
Can you attach an example data pack this issue can be reproduced with?
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Cannot reproduce in 26.2.
The loot is dropped onto the ground correctly.
Make sure you’re not testing your advancement in creative mode, as creative mode player can pick up dropped items and delete them when the inventory is full.