Why are the lines not displayed correctly in the assembly?

Question

Game development

Good evening.
I figured out how to set the desired color for the lines of the playing field ( https://toster.ru/q/277335)
I assembled the build, launched it - the lines are still pink in the game. When run inside the editor - the lines of the desired color (black).
What could be the problem?
Line drawing code:

private void DrawLine(Vector3 start,  Vector3 stop, GameObject template)
    {
        GameObject toInstiateGridLine = template;
        GameObject gridLineInstance = Instantiate(toInstiateGridLine, start, Quaternion.identity) as GameObject;
        LineRenderer gridLineRenderer = gridLineInstance.GetComponent<LineRenderer>();
        gridLineRenderer.material.color = Color.black;
        gridLineRenderer.SetVertexCount(2);
        gridLineRenderer.SetWidth(0.01f, 0.01f);
        gridLineRenderer.SetColors(Color.black, Color.black);
        gridLineRenderer.SetPosition(0, start);
        gridLineRenderer.SetPosition(1, stop);
    }

Game:

Assembly:

In addition, there is a feeling that the center lines are thicker than others. I would be grateful for any answer.

Answer 1

this is the color of lines without material. add material to linerender.
For example:

gridLineRenderer.material=new Material(Shader.Find("Unlit/Color"));

Answer 2

assembly can be in different folders .. and resources are different ... for example, an old shader is lying around somewhere