Block textures are broken and random. When rendering block textures in the world the player experiences the incorrect result for these textures. Old textures, the red glowing obsidian, are present.
Textures belonging to smaller blocks and items are on standard 16 cubic textured blocks. As seen in the short video, instances of the lever item texture are 16x16x16 texture blocks. Also, the lantern texture is on 16 cubic textured blocks.
Mobs are unaffected by this bug (currently). Flat textures such as spawn eggs or sea grass are unaffected. The item held in the longer video is a calibrated sculk sensor. The amethyst portion of the calibrated sculk sensor is bug results in the rendering of a Cactus. The cactus sculk streaker is in the longer video. Miscellaneous textures are also present; this can be seen with the yellow blocks with holes in them.
Shorter video (about 40 seconds)
https://drive.google.com/file/d/1lSk2fcC6kkmrjygccxNHqQmfcpZxLjVQ/view?usp=drivesdk
Longer video (about 1.5 minutes)
https://drive.google.com/file/d/1GjIwWH1FExysZIH4qlZOHs3ROqtA5q0e/view?usp=drives
This should be a main MCPE bug however I was unable to select it for the report.
Linked issues
Comments 1

Thank you for your report!
We're tracking this issue in MCPE-149662, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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