Found the same thing, this also happens during sliding, and is much easier to see during it, likely due to infinite rounds using the same code as sliding.
To add on to this specifically with the cart and counterspell if it's upgraded the cart will still stun the player even if they successfully counterspelled and didn't get moved
slide --> jump will cancel the slide taking priority of jump
dash --> jump will let you jump at any time
dash --> slide --> the jump button becomes impossible to press for a second or two, until a bit after the slide has ended
i feel like the jump should still be allowed as a dash in front of...