This mod fixesthe wonky behavior introduced in Minecraft 1.8.4 that displays critical particles (blue for sharpness, white on critical hit) client side, when this should be handled server-side. And this IS handled server side! Hence the particles are displayed twice.
This mod is compatible and tested with Forge 1.8, 1.9, 1.10, 1.11 and 1.12
The code itself is quite simple as it relies on the AttackEntityEvent event, called right before the particles are
displayed.
When using the mod, only valid hits trigger particles. Without it, this happens:
This is when hitting a static entity. Imagine how this feels during a combat!
Place this jar file in your mods folder, and you're done.
The mod register a Plugin Message channel, ParticlesFix. Servers are able to disable the behaviour of this mod by
sending this byte message: new byte[]{0x00, 0x00};.
The first 0x00 is the discriminator (the message's ID), the second one is the byte representation of false.
Use this mod at your own risk.