Not a game-breaker. And I've only tested this in 1.15. As far as I can tell from searching, no one else has reported this, either.
I have an AFK fish farm on a singleplayer/LAN world. (That works either way) And whenever I catch a fish, The rain comes through and is rendered in the building. As I'm creating this post, we also figured out that it's not an issue with fishing, it is triggered by a player collecting XP. My sister is connected via LAN and as I attempted to capture footage of the bug, she was triggering the glitch on my screen by collecting XP after killing a zombie.
Again, not a big deal in the gameplay sense, just thought it should be brought to attention.
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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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