Why is the Development Build extremely slow (even with a very simple scene)?

I’m trying to learn how Development Build works, so I created a very simple scene and built it with the Development Build option ticked.

However, when I start the game exe. (and the game opens up the Profiler window in Unity), the game runs extremely slow, so slow that it feels like I have a massive open world game with millions of polygons.

So why is it doing this? Does this happen to you as well or do I have to adjust some settings in my Unity?

It could be a problem specific to your project. Once I had a project where I would try to load a material during Start() but this one material couldn’t be loaded for some reason, but it never gave any errors and the FPS dropped tremendously without me knowing why at first. So, there could be problem’s “under the hood”, so to speak. Also, have you tried assembling a build, running it, and checking the outputlog for any errors that wouldn’t appear in the console?

this works for me