Please start testing Unity on bigger projects, we hit more and more bugs with every new unity release. Even the new job system + multi threading seems to be hogging systems down instead of improving performance. We'd happily share our project Verdun to this end but would need a point of contact to work together on these Unity bugs. (Case 736077) Editor scene editing too slow due to GISceneManager.Update When opening any of our scenes, the editor is very slow because GISceneManager.Update is running at 200-500MS according to the profiler (We are NOT even using GI). After 10+ minutes it will stop and the scene editing performance is back to normal again. However, (saving) and reopening the scene it will ALWAYS trigger this GISceneManager.Update again for 5 - 15 several minutes. (Case - none yet) Jobs system is hogging systems down instead of improving performance. Performance goes down with every extra multi threaded component Making a repro case today.