Normally, if you walk, no particles are shown. If you start running, particles depending on the block you're standing on get spawned. But if you stop, they should disappear instantly.
Instead if you sneak while you're running, the particles keep spawning as long as you move - whether by sneaking, walking or running.
Thank you for your report!
We're actually already tracking this issue in MC-152728, 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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