We have always discourage people from using the Customizer to inject site-wide css code. Instead we promote the use of their child-theme. This is because:

1. It's hard to maintain the css code in the Customizer and there is no version control (eg. once you delete/change something there is no turning back).
2. The changes are not properly tested in a dev/local environment first. They usually just get applied directly to production.
3. It makes it hard for the Planet 4 team to recognize and predict potential conflicts when we do UI changes, compared to looking the code in a child theme github repository.

Tasks

• Create a post-deploy script or migration script to delete any code already in the Customizer.
• Remove the option completely from the Admin Panel. We should leave the option only on dev sites for people to be able to prototype things.
• Document steps in more detail to do css customizations and use the dev site to test things out.