Directional Light missing when changing scenes

I made a basic Unity scene with a character (mainScene) and then another scene with a UI button (menuScene) so that when I press this button in menuScene, the mainScene is loaded:

public void startSimulation()

The mainScene has a directional light that is always there by default, but when I press the button in Editor mode, mainScene loads in a dark state. This does not happen when I build…

What am I missing or doing wrong?

This is a known bug that still persists in version 5.1.1f1