Steps to reproduce:

• Create a general empty project
• Open Content Library - User Assets
• -> 2D User assets section shows text "To use 2d, add the QtQuick3D module and the View3D component in the Components view, or click here". See attached picture.
• My assumption is that 2D Assets should be visible and usable without QtQuick3D import. If there are no 2D assets, placeholder text could be the same as in Textures section: "There are no items in this category."