Bubbles appear at the feet of drowning mobs

Can confirm in 21w03a.

Can confirm in 21w05b.

Can confirm in 21w06a. Video attached.

Can confirm in 21w07a.

Can confirm in 21w16a.

Can confirm in 1.17.

This is the code I believe spawns the bubble particles while an entity drowns.

net.minecraft.world.entity.LivingEntity.java (1.18.1, Mojang mappings)

...
    @Override
    public void baseTick() {
        ...
            if (((Entity)this).isEyeInFluid(FluidTags.WATER) && !this.level.getBlockState(new BlockPos(this.getX(), this.getEyeY(), this.getZ())).is(Blocks.BUBBLE_COLUMN)) {
                ...
                if ($$3) {
                    ...
                    if (this.getAirSupply() == -20) {
                        ...
                        for (int $$5 = 0; $$5 < 8; ++$$5) {
                            double $$6 = this.random.nextDouble() - this.random.nextDouble();
                            double $$7 = this.random.nextDouble() - this.random.nextDouble();
                            double $$8 = this.random.nextDouble() - this.random.nextDouble();
                            this.level.addParticle(ParticleTypes.BUBBLE, this.getX() + $$6, this.getY() + $$7, this.getZ() + $$8, $$4.x, $$4.y, $$4.z);
                        }
                        ...
                    }
                }
                ...
                }
            }
            ...
        }
        ...
    }
...

More specifically:

this.level.addParticle(ParticleTypes.BUBBLE, this.getX() + $$6, this.getY() + $$7, this.getZ() + $$8, $$4.x, $$4.y, $$4.z);

Instead of this.getY(), it should use this.getEyeY() so that the particles would be spawned at the entity's eye height.