Feature: #108240 - Introduce Fresh theme

Description

The new Fresh theme has been introduced for the TYPO3 backend, marking the beginning of broader backend customization capabilities. This theme offers users a modern alternative appearance option with a friendlier purple accent color palette.

Built on the modern CSS architecture, the Fresh theme is now the default for new users. It complements the existing Modern and Classic themes - all three themes will be maintained and enhanced equally going forward.

The extensive CSS framework improvements made during the 14.0 cycle now enable easier theme adaptation with minimal code changes, setting the foundation for the expanding theme system.

Theme Selection

Users can select their preferred theme in the User Settings module under the Backend appearance section. The Fresh theme provides a more contemporary look and feel while maintaining the familiar TYPO3 backend structure and usability.

All existing themes remain fully supported:

Fresh (default for new users) - Modern purple accent colors
Modern - Contemporary appearance with traditional accent colors
Classic - Traditional TYPO3 backend appearance

Future Development

Additional customization options and modern UI elements will be incrementally added to the theme system leading up to the LTS release. The modular CSS architecture ensures that all themes benefit from these enhancements equally.

Important

The backend CSS framework is currently considered internal API. No public CSS variables or settings have been defined yet that are guaranteed to remain stable across future versions. Areas such as color palette generation, accent colors, stateful colors, and tinting mechanisms are still in active development and subject to change before a long-term solution is established.

Impact

The introduction of the Fresh theme demonstrates TYPO3's commitment to providing a modern, customizable backend experience. The modular CSS architecture allows for continuous improvement and evolution of the backend design system.

New TYPO3 installations will automatically use the Fresh theme, while existing users can opt-in through their User Settings. The choice of theme is stored per-user, allowing teams with different preferences to work comfortably within the same TYPO3 installation.