When placing blocks if the selected block becomes obstructed (e.g. by another player or villager) at the same time you are placing it, it will disappear. It will be gone from your inventory as well, however will return to your inventory/ be placed once placing other blocks for example.
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violine1101
migrated
Thank you for your report!
We're tracking this issue in MC-163637, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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