The potion textures in the brewing stand are still the old textures. Here's how to notice it:
Find a brewing stand
Put any potion that is not a splash or lingering potion
Notice that there is still one pixel from the potion texture not covered by the potion
Thank you for your report!
However, we are already tracking this issue, and this report is a Duplicate of MC-150784, which is a report that has not been resolved yet.
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