If you swim into a 1 block night area you will crawl (land swim). When you go into 3rd person, you will mostly see black, like in the photo I provided. You will also have the walking particles bellow you
How to reproduce
make a long 1x1 tunnel
put on one end a hole in the top
put water in the hole
swim into it
when the water ends, you will keep swimming.
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We're tracking this issue in MCPE-93080, so this ticket is being resolved and linked as a duplicate.
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