Potions of Slowness and Turtle Master are indistinguishable in cauldrons

When a potion of the Turtle Master is placed in a cauldron, it is indistinguishable from a potion of Slowness, including the particles produced.

Steps to reproduce:

Place two cauldrons down, and put three potions of the Turtle Master in one and three potions of Slowness in the other

Expected behavior:

The color of the potion and particles of the Turtle Master would be purplish like the potion itself. (Or possibly the potion water would be purple like the potion and the particles would be some resistance-purple colored and some slowness-bluish like the particles of a player who drank a Turtle Master potion)

Observed behavior:

The Turtle Master cauldron is the same bluish color of the Slowness cauldron, including the particles.

(The photo has each potion in the cauldron, plus arrows of the respective effects for particle comparison. You can see that the particle from the Turtle Master cauldron is the same as the ones from the Slowness arrow)