TextGenerator with Canvas Scaler

Hello,

First my relevant Code

 TextGenerator textGen = textToEdit.cachedTextGenerator;
 
         for (int k = 0; k < textGen.GetCharactersArray().Length; k++)
         {
             GameObject obj = GameObject.Instantiate(prefab);
             
             float x = textGen.GetCharactersArray()[k].cursorPos.x;
             float y = textGen.GetCharactersArray()[k].cursorPos.y;
             obj.transform.SetParent(textToEdit.transform);
             obj.transform.localScale = new Vector3(2f, 2f, 1f);
             Vector3 imagePos = new Vector3(x, y, 0);
 
             obj.transform.localPosition = imagePos;
         }

This creates small little red dots for each Symbol in a UnityUI.Text element [Image1]. This works fine if my UI Canvas Scaler is set to Constant PIxel Size.

But when i turn the Canvas Scaler to Scale With Screen Size, X:1280, Y:720 and Match:1 I get a distransformed result, which seems "wrong" to me. [Image2]

And on my Mobile device its even distorted in the Y-Axis

Any Idea with what factor i have to scale X and Y to get me the same results as in Image 1 while using Scale with Screen Size ?