Unnecessary stuff inside .fbx after importing?

After i import .fbx from blender and click the little arrow beside the icon in the project window, it shows duplicate meshes.

In this scene, I edited the two cube meshes but not the plane, so only the cube meshes got duplicated. Should I worry about it? Is there something I am missing when exporting out of blender? Also what is the last icon labelled "avatar"?

 

The Avatar is basically a description of the skeleton. You'll get one if an FBX you export contains a skinned mesh (aka an Object with the Armature modifier in Blender + valid Armature).

The duplicates that have identical names are different things:

• The first "Cube" is a GameObject with a MeshRenderer component rendering a cube
• The second "Cube" is the mesh data (vertices, normals, UVs, faces)

If you use duplication by reference in Blender (Alt+D), where multiple Blender objects reference the same vertex data, you would see two Cube objects in Unity but only one Cube mesh.

So all is like it should be. The only slightly unusual thing I can spot is that the "Plane" mesh data doesn't seem to be used anywhere.

 

Ah I see, thanks! The plane is just to store the position info. Im attaching another gameobject to it in unity.