The animation renders too dark on one side of the block, and it renders in strips on another. It also seems sped up. However, if you stand further away from the block, the texture seems normal (if a bit darker.) It also may temporarily stop happening, or it may only happen with blocks eye level to the player.
Thank you for your report!
We're actually already tracking this issue in MC-163045, so I resolved and linked this ticket as a duplicate.
However, that ticket has already been resolved as Fixed. The fix will arrive in the next version or is already included in the latest development version of the game.
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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