Click on the More section, then you can find the option for “Devices”.
There you can choose to show the pre-loader on which type of devices. It allows you to hide the preloader on mobile devices, or create a splash/launch screen on mobile devices only.
Please note: the options in the More section only work on front end. It means when you change the settings, nothing will happen in the preview area. Save the changes you have made, they will be applied to your site. Please remember to clear your site cache and browser cache before checking your front-end.