Minitable empty state

[benjaminleonard]

Currently the mini table is not rendered if it has no items.

An empty state here would be a bit clearer, and would also help mitigate #2627 by showing the user that it has not yet been selected.

I tried versions with and without the icon. The icon is nice, but I think it's inclusion would cause extra layout shift when the first item is added which might be distracting.

[david-crespo]

I think I like it better without the icon regardless of pop-in. The green is too eye-catching.