In the Visual Composer Dashboard, you can update various Global Settings directly from your WordPress Admin Panel.
Disable preview option allows you to easily disable preview and description of elements and templates that are already added to your list.
As a pro or regular user of the Visual Composer, you may know all the elements and templates in your list by heart. As a result, there is no need to see element preview and description upon hover.
To disable the preview option, go to the Visual Composer Dashboard, find Settings and disable the preview toggle.
Note: You will still see element and template preview in the Visual Composer Hub.