[later phase] Determine process for allowing theme customization for starshot users

SDC is a great starting point but:

• SDC is not exposed to display builders (block layout, manage display, layout builder, view display...)... yet
• A design is not only made of components. To build a complete display, we need to expose and manipulate other design artefacts: style utilities, variables, UI themes, iconsets...

I am available to share with you how we achieve that with UI Suite: https://www.drupal.org/project/ui_suite →

@pdureau I agree with what you're saying, I think SDC is just a part of the puzzle for customizing bits and pieces.

E.g. adding an accordion and being able to swap out the front end piece for a different SDC would be great.

I think that before we can move forward with this, we need to clarify what will be the role of Experience Builder in this space. I cannot imagine a first-in-class page building experience that doesn't implement all of those features.

IMHO, we need those 3 layers:

1. declaration of design systems artefacts in YML. We already have the beloved SDC for components. We need to cover the others: Style utilities, CSS variables, UI themes/modes, iconsets..
2. mechanism to convert those artefacts to configurable plugins (blocks, layouts, field formatters...), or to alter configurable plugins. This is what UI suite modules are doing: ui_patterns → for components, ui_styles → for style utilities, ui_skins → for CSS variables and UI themes/modes...
3. experience builder is using those configurable plugins. The one coming from the design system artefacts, but also the ones coming from other API (blocks derived from views or menu for example)

I think this will be up to Experience Builder. Let's move it back to Starshot if Experience builder is not the answer :)

The issue comes from a slack discussion which was in essence. Let's put UI suite in starshot to let users try the "site build able components" parts of XP builder now rather than later. So a bit redundant to put that here imo, but it can't hurt

See #3450621-6: [later phase] Theme Builder vision → .