I've noticed that with the new update while a character walks next to a block hanging above empty space of 1 block high, it sinks down and assumes the swimming position.
The sinking in has had happened to me few times already on dirt, stone and gravel blocks.
Thank you for your report!
We're actually already tracking this issue in MC-177970, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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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