[Boot2Qt ] 'Failed to build graphics pipeline' when running 'orderindependenttransparency' example

Failed to compile shader: 0:2(12): error: extension `GL_OES_sample_variables' unsupported in fragment shaderSource was:
#version 300 es
#extension GL_OES_sample_variables : require
precision highp float;
precision highp int;uniform highp sampler2DMS accumTexture;
uniform highp sampler2DMS revealageTexture;in vec2 uv_coord;
layout(location = 0) out vec4 fragOutput;void main()
{
    vec2 uv = uv_coord;
    ivec2 iuv = ivec2(uv * vec2(textureSize(accumTexture)));
    vec4 accum = texelFetch(accumTexture, iuv, gl_SampleID);
    float a = 1.0 - texelFetch(revealageTexture, iuv, gl_SampleID).x;
    vec4 color = vec4(accum.xyz / vec3(clamp(accum.w, 9.9999997473787516355514526367188e-05, 5000000.0)), a);
    fragOutput = color;
}
Failed to build graphics pipeline state