Build script to strip out Colliders from a scene, used in a project where all static colliders we exported as a json file and were not needed within the scene at runtime which made it more performant.

Unity3D_CleanupSceneBuildProcessor.cs

#if UNITY_EDITOR

/**
This script should be located in an Editor folder
No need to try assigning it to a GameObject
It will run automatically when playing from the editor or during a build
see: https://docs.unity3d.com/ScriptReference/Build.IProcessSceneWithReport.OnProcessScene.html
*/

using System;
using System.Text;
using UnityEditor.Build;
using UnityEditor.Build.Reporting;
using UnityEngine;

public class CleanupSceneBuildProcessor : IProcessSceneWithReport {

    // set to false to disable this script
    bool processScenes = true;
    bool VERBOSE = true;
    StringBuilder logBuilder;

    string[] includeSceneNames = new string[] {
        "Level1",
        "Level2",
        "Level3"
    };

    string[] excludeGameObjectNames = new string[] {
        "Ground"
    };

    public int callbackOrder { get { return 0; } }

    public void OnProcessScene (UnityEngine.SceneManagement.Scene scene, BuildReport report) {
        if (!processScenes) return;

        // process whitelisted scenes
        if (Array.IndexOf (includeSceneNames, scene.name) > -1) {
            if (VERBOSE) logBuilder = new StringBuilder ("MapBuildProcessor.OnProcessScene " + scene.name).AppendLine ();
            var rootObjects = scene.GetRootGameObjects ();
            Array.ForEach (rootObjects, HandleCollidersInChildren);
        }

        // output log result, if available
        if (logBuilder != null) {
            Debug.Log (logBuilder.ToString ());
            logBuilder.Clear ();
        }
    }

    void HandleCollidersInChildren (GameObject obj) {
        var colliders = obj.GetComponentsInChildren<Collider> ();
        Array.ForEach (colliders, (collider) => {

            if (HasTransformAndColliderOnly (collider.gameObject)) {
                if (VERBOSE) logBuilder.Append ("  > Destroyed GameObject " + collider.gameObject.name + " from parent: " + collider.transform.parent.name).AppendLine ();
                GameObject.DestroyImmediate (collider.gameObject);

            } else if (Array.IndexOf (excludeGameObjectNames, collider.gameObject.name) == -1) {
                if (VERBOSE) logBuilder.Append ("  > Disabled Collider Component: " + collider.gameObject.name).AppendLine ();
                collider.enabled = false;
            }
        });
    }
    
    // custom rule: remove nested gameobjects that only contain a collider script
    bool HasTransformAndColliderOnly (GameObject gameObject) {
        return (
            gameObject.GetComponents<Component> ().Length == 2 &&
            gameObject.GetComponent<Transform> () != null &&
            gameObject.GetComponent<Collider> () != null
        );
    }
}

#endif