Introduces new color properties for the URL bar and tab strip in all themes, updates the theme system and CSS to support these, and ensures the renderer applies the correct colors to the main UI. This allows each theme to fully customize the appearance of the URL bar and tabs for a more cohesive look.
Introduces a full browser customization system with support for theme presets, live editing, import/export, and non-destructive design. Adds new documentation for customization, updates the features list, and implements a ThemeManager for loading and managing themes at the application level. Updates home and settings pages to support live theming and preview, and adds four built-in themes (default, forest, ocean, sunset).
andrew