In the 3D viewport you can press the shortcut and drag your mouse left and right to rotate the hdri background. This is useful for changing the lighting quickly.




You can change the shortcut in the addon preferences. Here you can also deactivate it entirely.

While the shortcut is usally only active when you are on Layer Painter instead of Default, you can check Always Active to keep the shortcut even if you are on Default. The default shortcut is Shift+Rightclick.