Scripted detaillayer prototypes won't show in build.

Hello there,

I've found an issue with the terrain detaillayers. Script-added detaillayer prototypes won't show in the windows build.

As a test i've created the detaillayers in following way:

1) Added detaillayer prototypes trough the terrain tools (both textures and vertex-lit).

2) Added detaillayer prototypes to the same terrain with the following script (snippet):

     DetailPrototype[] oldDetailPrototype = terrain.terrainData.detailPrototypes;
     DetailPrototype[] newDetailPrototype = new DetailPrototype[(terrain.terrainData.detailPrototypes.Count() + gameObjectList.Count())];
     int[] referencelist = new int[gameObjectList.Count()];
     
     for (int i=0;i<terrain.terrainData.detailPrototypes.Count();i++) {
         newDetailPrototype[i] = oldDetailPrototype[i];
     }
     
     int counter = 0;
     int j = terrain.terrainData.detailPrototypes.Count();
     foreach(GameObject obbie in gameObjectList) {
         DetailPrototype prototype = new DetailPrototype();
         prototype.prototype = obbie;
         prototype.dryColor = Color.black;
         prototype.healthyColor = Color.black;
         prototype.noiseSpread = 0.1f;
         prototype.renderMode = DetailRenderMode.VertexLit;
         prototype.usePrototypeMesh = true;
         prototype.minWidth = 0.75f; 
         prototype.maxWidth = 1.0f;
         prototype.minHeight = 0.75f;
         prototype.maxHeight = 1.0f;
         newDetailPrototype[j] = prototype; 
         referencelist[counter] = j;
         j++;
         counter++;
     }
     
     terrain.terrainData.detailPrototypes = newDetailPrototype;
     terrain.terrainData.RefreshPrototypes();
     terrain.Flush();

3) Both the tool-added and the script-added detail prototypes are then assigned trough a script to the detaillayers.

4) In the Unity editor both the tool-added and the script-added details appear on the terrain on runtime.

5) In a build only the tool-added details appear on the terrain on runtime

The runtime error log shows no errors or notices regarding this what so ever. Adding the prefabs in the resource folder makes no difference.

Do you have any idea why this issue appears? And do you have a possible solution for this?

Thanks in advance!