The splash screen only appears on pages with video backgrounds or parallax effect. These pages usually load a considerable amount of time and the splash screen is a valuable addition.

How to edit the splash screen:

The background of the splash screen is attached to an accent colour in Dashboard > Appearance > Customize >  Global Styles > Accent 8

You can change the logo in Dashboard > Appearance > Customize > Site Identity > Splash Screen Logo

How to enable/disable the splash screen:

You can enable or disable the splash screen in the page's local Vamtam options.