Description
Custom Fields allow you to add additional metadata to pages and posts. By default, custom fields are disabled and have to be manually enabled before you can use them.
How to Enable & Create Custom Fields
When editing a page or post, click the three-dot button on the top right side of the editor.
Navigate to Preferences > Panels, then toggle on Custom Fields.
To create custom fields, navigate to Foundry > Custom Fields.
Screenshots
Advanced
Additional CSS Class(es)
This allows you to enter a unique Class identifier, for custom CSS targeting within the theme to faciliate custom development. More about Theme Customizations.
It also enables the use of Foundry utility classes. More about Utility Classes.