Using TextGenerator

For those who are still searching how to use the TextGenerator class:

I personally had some problems setting up the TextGenerationSettings. When you create your own TextGenerationSettings, it has no sensible default values
(probably something to do with it being a struct, but on the same note, not sure why it was decided to make this fairly large container into a struct even though you can end up passing it to the TextGenerator a lot of times, forcing a copy of all the values inside).
Bellow is just an example of the settings I ended up using in my tests but some important ones to not miss are lineSpacing and scaleFactor as the default 0 values can mess up the vertex positioning a lot.

 var m_TextSettings = new TextGenerationSettings();
 
 m_TextSettings.textAnchor = TextAnchor.MiddleCenter;
 m_TextSettings.color = Color.red;
 m_TextSettings.generationExtents = new Vector2(100, 100);
 m_TextSettings.pivot = new Vector2(0.5f, 0.5f); ;
 m_TextSettings.richText = true;
 m_TextSettings.font = m_Font;
 m_TextSettings.fontSize = 14;
 m_TextSettings.fontStyle = FontStyle.Normal;
 m_TextSettings.verticalOverflow = VerticalWrapMode.Overflow;
 m_TextSettings.horizontalOverflow = HorizontalWrapMode.Wrap;
 m_TextSettings.lineSpacing = 1;
 m_TextSettings.generateOutOfBounds = true;
 m_TextSettings.resizeTextForBestFit = false;
 m_TextSettings.scaleFactor = 1f;

As mentioned in one of the comments, if you are using a CanvasRenderer, you need to set material and mesh:

 m_CanvasRenderer.SetMaterial(m_Font.material, null);
 m_CanvasRenderer.SetMesh(m_Mesh);

If you are using a MeshRenderer, you probably want a MeshFilter component as well and assign a new mesh to it:

 GetComponent<MeshFilter>().mesh = m_Mesh;
 m_MeshRenderer.sharedMaterial = m_Font.material;

To generate a mesh from TextGenerator, I made this extension method:

 public static class TextExtensions
     {
         static public void GetMesh(this TextGenerator i_Generator, Mesh o_Mesh)
         {
             if (o_Mesh == null)
                 return;
 
             int vertSize = i_Generator.vertexCount;
             Vector3[] tempVerts = new Vector3[vertSize];
             Color32[] tempColours = new Color32[vertSize];
             Vector2[] tempUvs = new Vector2[vertSize];
             IList<UIVertex> generatorVerts = i_Generator.verts;
             for (int i = 0; i < vertSize; ++i)
             {
                 tempVerts[i] = generatorVerts[i].position;
                 tempColours[i] = generatorVerts[i].color;
                 tempUvs[i] = generatorVerts[i].uv0;
             }
             o_Mesh.vertices = tempVerts;
             o_Mesh.colors32 = tempColours;
             o_Mesh.uv = tempUvs;
 
             int characterCount = vertSize / 4;
             int[] tempIndices = new int[characterCount * 6];
             for(int i = 0; i < characterCount; ++i)
             {
                 int vertIndexStart = i * 4;
                 int trianglesIndexStart = i * 6;
                 tempIndices[trianglesIndexStart++] = vertIndexStart;
                 tempIndices[trianglesIndexStart++] = vertIndexStart + 1;
                 tempIndices[trianglesIndexStart++] = vertIndexStart + 2;
                 tempIndices[trianglesIndexStart++] = vertIndexStart;
                 tempIndices[trianglesIndexStart++] = vertIndexStart + 2;
                 tempIndices[trianglesIndexStart] = vertIndexStart + 3;
             }
             o_Mesh.triangles = tempIndices;
             //TODO: setBounds manually
             o_Mesh.RecalculateBounds();
         }
     }

Hope this helps some people;