Getting error when using Shader material with instancing support

Hello guys,

Following is my vertex shader…

precision highp float;
// Attributes
attribute vec3 position;
attribute vec2 uv;
attribute vec4 world0;
attribute vec4 world1;
attribute vec4 world2;
attribute vec4 world3;

// Uniforms
uniform mat4 view;
uniform mat4 viewProjection;

varying vec2 UV;

void main(void) 
  mat4 world = mat4(world0, world1, world2, world3);
  mat4 worldViewProjection = viewProjection * world;
  gl_Position = worldViewProjection * vec4(position, 1.0);
  UV = uv;

and fragment shader…

    precision highp float;

// Varying
varying vec2 UV;
uniform sampler2D albedo;

void main(void) {
    gl_FragColor = texture(albedo,UV);

and this is how I create shader material…

this._trackMaterialInstanced = new ShaderMaterial('trackMaterial',this._scene, "./assets/shaders/opaque_instancing", {
      attributes: ["position","uv", "world0", "world1", "world2", "world3"],
      uniforms: ["viewProjection","albedo"]
    const albedo = new Texture('assets/textures/Atlas_Opaque_Arctic.png', this._scene);
    this._trackMaterialInstanced.setTexture('albedo', albedo);
    this._trackMaterialInstanced.backFaceCulling = true;
    this._trackMaterialInstanced.forceDepthWrite = true;

I am getting following error in my game after a while…

thinEngine.js:2931 Uncaught TypeError: Cannot read property 'program' of null babylon js

Any idea what I am doing wrong? Thanks.

See your other thread about the same subject where you can find a working PG.

looks like a dup of How to add instancing support in Shader Material? could you share a playground there to troubleshoot ?

It seems like shader program is getting destroyed. But anyways, I will create a PG.