With the enchantment refactors in the most recent snapshot at the time of writing, Soul Speed appears to trigger when the player is "unsupported." Cases include swimming, climbing scaffolding, and falling in the air.
To reproduce:
enter a save.
acquire and equip boots enchanted with soul speed.
run or walk while jumping and/or falling off of blocks.
notice the momentary speed increase when air is below the player. If FOV effects are enabled, this will be obvious and jarring due to the FOV effect that occurs when speeding up.
Linked issues
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Thank you for your report!
We're actually already tracking this issue in MC-271422, so this ticket is being resolved and linked as a duplicate.
If you would like to add a vote or any additional information to the main ticket it would be appreciated.
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