Description

The Global Style Typography panel displays an unnatural border when the theme does not define a font.

I'm wondering if it would be a good idea to display a copy like below if the font doesn't exist.

This is similar to the UI when there is no custom color palette.

Step-by-step reproduction instructions

• Enable EmptyTheme. This theme does not define any fonts.
• Open the site editor and access the Global Styles Typography panel.
• You should now see a border in the Fonts section.

Screenshots, screen recording, code snippet

No response

Environment info

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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