The slime and magma cubes jump interval while seem broken after the 1.18, when they are chasing a player, the slimes usually rest for a few ticks before jumping next, and the magma cubes will rest for about 4 seconds and even more longer. Before the 1.18, they moving more faster if they are chasing a player, according to my test, the slime almost not rests and the magma cubes rests for two seconds at most.

I was tested in 1.17.1 and 1.18.2 that showing their jump interval.