Description

This might have been an intended design change, but my basic design instincts are telling me not given the way all other content in the sidebar is aligned top.

Step-by-step reproduction instructions

1. Insert a block that only supports a few limited inner blocks (e.g. list, button)
2. Try inserting inner blocks with that parent using the main sidebar
3. Observe that the inserter items are vertically centered

Screenshots, screen recording, code snippet

Environment info

• Mac OS / Brave
• Latest Gutenberg trunk

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