Script to Limit framerate of unity editor, add to any GameObject to use

FramerateLimiter.cs

// Based on LLeaLoo's script
#if UNITY_EDITOR
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEditor;

public class FramerateLimiter : MonoBehaviour
{
    public int targetFrameRate = 30;
}

[CustomEditor(typeof(FramerateLimiter), true)]
public class FramerateLimiterEditor : Editor
{
    private FramerateLimiter my;

    public override void OnInspectorGUI()
    {
        my = (FramerateLimiter) target;

        this.DrawDefaultInspector();
        GUILayout.Label("Current Target Framerate: " + Application.targetFrameRate.ToString());

        if (GUILayout.Button("Update Target")){ SetTargetFramerate(); }
    }

    void SetTargetFramerate()
    {
        my = (FramerateLimiter) target;

        QualitySettings.vSyncCount = 0;  // VSync must be disabled
        Application.targetFrameRate = my.targetFrameRate; // Use -1 to set back to default
    }
}
#endif