What I think is intended:
A walking sneaking player should not cause particles to appear(provided they don't jump)
What happened:
If you hold the sprint key and press the sneak key while holding that sprint key, you will sneak but create particles under you.
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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