Strange problem with shader

Unity Engine
1

I have simple shader from CG tutorial:

struct v_Output {
	float4 position : POSITION;
	float4 color    : COLOR;
};

v_Output vert(float2 position : POSITION)
{
	v_Output OUT;
	OUT.position = float4(position, 0, 1);
	OUT.color    = float4(0, 1, 0, 1);
	return OUT;
}

struct f_Output {
	float4 color : COLOR;
};

f_Output frag(float4 color: COLOR)
{
	f_Output OUT;
	OUT.color = color;
	return OUT;
}

In one project it works fine, but if I copy the shader to my old project it doesn’t work as I expected.

2

Complete shader code? (Starting with “Shader”)