If the player is inside an enclosed area while it is currently raining/snowing, and they remove a stacked item from a furnace/smoker/blast furnace, then for a brief moment, the rain would render even though the rain is blocked by the walls surrounding the player. It would seem only to affect the furnace variants.
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Thank you for your report!
We're actually already tracking this issue in MC-163575, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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