Spacer Plugin Bug?

One tip: you can quickly clone spacers using Drag&Drop. Hold down the CTRL key and drag the spacer into any space. In this case you will get the same spacer in other place

I was expecting a new Spacer picture, once selected, to be insertable with the ease of inserting a Separator. Is Yuri saying this is not the case because he uses a different definition of Spacer than I do? I think that's great, but I don't understand where he wants to go with Spacers. Can you help me understand Yuri's vision better?

The spacer plugin is like separator. But this is plugin and every plugin have own settings. And this is not a separator. The only usage of spacer to add empty space into menus and toolbar. When you do not select any picture in the properties you can setup the size of empty space to be added.