Unity: Generate a quick scene-opening menu from the scene list of the Build Settings

SceneMenuGenerator.cs

using System.IO;
using System.Text;
using UnityEditor;
using UnityEngine;

// Generate a quick scene-opening menu from the scene list of the Build Settings.
// Usage: Open "Scene -> Generate Scene Menu..."
public static class SceneMenuGenerator
{
    // Customize it appropriately.
    const string GenerateCodePath = "SceneMenu.cs";
    const bool IncludeDisabledScenes = true;

    [MenuItem("Scene/Generate Scene Menu...")]
    public static void Generate()
    {
        var sb = new StringBuilder();

        // Header
        sb.Append(@"// Generated by SceneMenuGenerator.cs
using UnityEditor;
using UnityEditor.SceneManagement;

public static class SceneMenu
{
");
        // Generate menu items
        var index = 0;
        foreach (var scene in EditorBuildSettings.scenes)
        {
            if (!IncludeDisabledScenes && !scene.enabled) continue;

            var menuItemName = Path.GetFileNameWithoutExtension(scene.path);

            sb.Append($@"    [MenuItem(""Scene/{menuItemName}"", false, priority = {100 + index})]
    public static void OpenScene{index}() => OpenScene(""{scene.path}"");
");
            index++;
        }

        // Footer
        sb.AppendLine(@"
    static void OpenScene(string path)
    {
        Selection.activeObject = AssetDatabase.LoadMainAssetAtPath(path);
        EditorSceneManager.OpenScene(path);
    }
}");

        File.WriteAllText(Path.Combine(Application.dataPath, GenerateCodePath), sb.ToString());
        AssetDatabase.Refresh();
    }
}