Minecraft wiki entry for Development_versions, associated text: The ravager now targets and attacks the wandering trader (MCPE-44606).
Mobs spawned from a dispenser are now persistent (MCPE-110521).
Shulkers no longer like to occupy the same block as another shulker (MCPE-43972).
Shulkers now prioritize attaching to neighboring block faces before trying to teleport away.
Shulkers now stay attached to the current attached blockface if it is valid, instead of switching to upright position.