Then the following things will have to be changed:
- Styles list in acp_styles will show all available styles as tree. Styles that are present in phpbb_styles table will be shown as installed, other styles will be shown as not installed.
- Style preview will use style path instead of id, allowing admins to preview styles before installing it.
- style_active field in phpbb_styles will be removed.
- "Install styles" section will be removed.
- Users will be able to select any installed style, unless override_user_style is enabled.
- It will require new class for styles tree, allowing forum to locate all parent styles when user previews style from path. Something like phpbb_styles_list