Allow multiple ParticleTextureBlock blocks

src/Materials/Node/Blocks/Particle/particleTextureBlock.ts

@@ -46,7 +46,7 @@ export class ParticleTextureBlock extends NodeMaterialBlock {
     public constructor(name: string) {
         super(name, NodeMaterialBlockTargets.Fragment);
 
-        this._isUnique = true;
+        this._isUnique = false;
 
         this.registerInput("uv", NodeMaterialBlockConnectionPointTypes.Vector2, false, NodeMaterialBlockTargets.VertexAndFragment);