Repro Steps:
Create a new World in Creative mode.
Spawn a Pillager Captain.
/summon minecraft:pillager ~ ~1 ~ {PatrolLeader: 1b, ArmorItems: [{}, {}, {}, {id: "minecraft:white_banner", Count: 1b, tag: {HideFlags: 32, BlockEntityTag: {Patterns: [{Pattern: "mr", Color: 9}, {Pattern: "bs", Color: 8}, {Pattern: "cs", Color: 7}, {Pattern: "bo", Color: 8}, {Pattern: "ms", Color: 15}, {Pattern: "hh", Color: 8}, {Pattern: "mc", Color: 8}, {Pattern: "bo", Color: 15}]}, display: {Name: '{"color":"gold","translate":"block.minecraft.ominous_banner"}'}}}], Attributes: [{Base: 0.0d, Name: "generic.maxHealth"}]}
Kill the Pillager Captain.
Observe that green particles does not appear around Player's model.
Bedrock's particles are this bug: MCPE-46641