New godot's "per-instance" feature is confusing

Question

So I've been truing to follow the official snapshot of these new cool per-instance uniforms in shaders and didn't quite understand it. When I add instance prefix, the hint_range just disappears and is nowhere found and my variable defaults to 0 (in shader's calculations).

I'm using it on sprite2D node

shader_type canvas_item;
instance uniform float opacity : hint_range(0,1) = 1;

void fragment(){
    vec4 color = texture(TEXTURE,UV);
    color.a-=opacity;
    COLOR = color;
}

/
Did anyone figure out what that means, did anyone meet the similar issue?

Answer 1

It looks like instance uniforms are only implemented for spatial shaders at the moment.

From Juan (the feature creator):

Oh just as a side note, per instance uniforms are not working for 2D (CanvasItems) because I could not find a way to implement them. I am planning to eventually rewrite the 2D rendering code to make it more efficient before 4.0 is out, now that I am more proficient with Vulkan so I will properly implement those there.

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