How to reproduce:
1. Open a new project
2. Press the "Auto Generate Lighting" quick button at the bottom right of the Editor
3. Press the same button again

Expected result: The Lighting window closes
Actual result: The Lighting window doesn't close

Reproducible with: 2019.4.13f1, 2020.1.11f1, 2020.2.0b9, 2021.1.0a3
Could not test with: 2018.4.28f1 (No quick buttons at the bottom right of the Editor)

Notes:
- The Generate Lighting button reproduces in the mentioned versions in the Reproducible section
- The Layers button works properly in 2018.4 and 2019.4, while it doesn't close the window when pressed in 2020.1, 2020.2. In 2021.1 it keeps re-opening it
- In 2021.1 the Global Search was introduced in the Toolbar, which doesn't close the window when pressed again