Vanilla bugs patched by this add-on

"MCPE-XXXXXX" below are keys to bug reports on Mojang's public bug tracker. You can read more about each bug on the associated report.

Behavior

Command related

MCPE-50328 Zombies spawned by /summon with events now have correct speed
MCPE-116971 Vindicator captains spawned by /summon are now hostile

Illagers

MCPE-34746 Evokers summon vexes more quickly (matches Java)
MCPE-42373 Vindicators and Evokers no longer retaliate when shot by Pillagers
MCPE-44454 Vexes spawned by evokers now spontaneously take damage after a period of time (matches Java)
MCPE-44606 Ravager now hostile toward wandering traders
MCPE-45531 Ravager collision box increased (matches Java)
MCPE-48145 Ravager movement speed increased (matches Java)
MCPE-45820 Vindicator and pillager wandering speed decreased
MCPE-50207 Ravager targeting range increased (matches Java)
MCPE-51329 Ravagers now break wither roses
MCPE-60680 Ravager attack reach increased (fixed by collision fix above)
MCPE-84371 Pillagers and Ravagers now hostile toward snow golems
MCPE-91598 Patrols once again swarm/attack as a group (this existed in 1.14 but was removed in 1.16)
MCPE-115094 Vexes no longer retaliate against evokers
MCPE-125322 Ravagers now break lush cave plants
MCPE-150960 Ravagers now break nether plants and vines

Ghast

MCPE-35202 Ghast fireball now comes from its mouth instead of the top of its head
MCPE-45311 Ghast no longer holds charge when player leaves its targeting range
MCPE-50207 Ghast targeting range increased horizontally and decreased vertically (matches Java)

Spawning/Despawning

MCPE-10240 Spiders now have a chance of spawning with status effect buffs on hard difficulty
MCPE-44312 / MCPE-102302 Trader llamas can now despawn if unleashed
MCPE-46540 Magma cubes no longer spawn in small spaces
MCPE-60859 Slimes no longer spawn in small spaces
MCPE-67452 Reduced ghast despawn/respawn frequency and skeleton and endermen densities in the nether
MCPE-87453 Patrols now spawn more reliably around villages, especially on simulation distance 4
MCPE-89549 Spiders can now spawn as stray and wither skeleton jockeys in appropriate biomes
MCPE-149883 Witches no longer despawn during raids

Villagers and Zombie Villagers

MCPE-57524 Clerics now sell glowstone instead of glowstone dust
MCPE-80924 Zombie villagers with custom textures no longer all look like farmers
MCPE-89210 Cured nitwit zombie villagers remain nitwits and cured nitwits and unemployed now sleep at night

Other Mob Behaviors

MCPE-35306 Enderman follow range increased (matches Java)
MCPE-35647 Blaze ranged attack range increased (matches Java)
MCPE-45756 Trader llamas no longer push the wandering trader around 
MCPE-48233 Fox health decreased (matches Java)
MCPE-51161 Zombified piglins anger broadcast range increased and zombified piglins that spawn near angry zombified piglins now become angry
MCPE-68327 Zombified piglins no longer call other zombified piglins when killed in one hit
MCPE-74081 Iron golems can now be repaired with iron ingots
MCPE-105369 Husk height decreased (matches zombies and other humanoids)
MCPE-137149 Skeletons converting to strays no longer generate armor on converstion
MCPE-138191 Blazes no longer avoid fire, magma, and campfires
MCPE-146651 Slimes are once again aggressive toward snow golems

Other

MCPE-24341 Armor stands no longer take damage from splash potions
MCPE-60895 Removed mob collision for lodged tridents (note: does not affect hitbox or functionality of trident killers)
MCPE-87711 Removed mob collision for XP orbs
MCPE-106439 XP now rises as fast as items and mobs in soul sand bubble columns
MCPE-109330 XP now sinks as fast as items and mobs in falling water
MCPE-127736 Lily pads are now fishing junk instead of fishing treasure
MCPE-134649 Item alignment with anvils in water streams now works in all directions

RESOURCE

Sound

MCPE-35222 Ghast sound volume lowers more noticeably with distance (now starts to attenuate at 24 blocks, used to be 100)
MCPE-43831 Trident loyalty return sound is more audible
MCPE-90160 Minecart sounds now stop at 16 blocks
MCPE-117964 Eggs now make a breaking sound when destroyed by a ravager

Other

MCPE-42348 Zombie villagers now show profession clothing
MCPE-45311 Ghast returns its face to normal when it does not have a target
MCPE-74081 Iron golems now show cracks when damaged
MCPE-91361 Red glass breaking particles now match other glasses
MCPE-114253 Squid/glow squid texture now aligned with its collision box
MCPE-110282 XP orb texture now aligned with its collision box (note: this does not fix desyncing)