Description

Part of #41236.

spacing.blockGap is mentioned in the supports section of the block API reference.

It says that setting the property to true is enough to enable the functionality if the theme supports it. This wasn't the case for me. Looking at the blocks which currently support blockGap, they either use layouts or use some gap specific hooks.

It would be great to have better documentation on how I can use blockGap in custom container blocks of my own.

Please confirm that you have searched existing issues in the repo.

Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

Yes