Block.json supports

Hi,

How does one specify whether or not a block control is shown in the block settings sidebar?

For example;
– We have a custom block with block.json that has supports ‘backgroundColor’ set to true.
– We have not preset any attribute (leave it to user).
– When the block is selected, the controls are hidden under the + sign in the block settings sidebar, can be enabled, and a color can be picked.

However, when we select a core/paragraph block for example. The background color module in the block settings is already opened, even thought no color is preselected.

I was hoping to get some feedback on how to get the controls ready and available on the block, without having to press the + first.

I have a terribly hard time finding it in the docs, or trying to figure it out from reading the paragraph code.