On 25w41a if you look at an ominous banner from the right angle then it will show the textures of other blocks and items.
The attached image shows this (they are ominous banners but the bug makes them look like white ones).
I cant reliably replicate the bug but just place down an ominous banner and run around it until you find the right angle. The expected result would be for it to have the regular ominous banner texture.
Environment
fighting illagers and building
Thank you for your report!
We're tracking this issue in MC-302669, so this ticket is being resolved and linked as a duplicate.
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