# theme_boost Upgrade notes ## 4.5 ### Added - Bridged `theme-color-level` using a new `shift-color` function to prepare for its deprecation in Boostrap 5. For more information see [MDL-81816](https://tracker.moodle.org/browse/MDL-81816) - Upon upgrading Font Awesome from version 4 to 6, the solid family was selected by default. Support for the `regular`, and `brands` families of icons has now been added, allowing icons defined with `\core\outut\icon_system::FONTAWESOME` to use them. Icons can select the FontAwesome family (`fa-regular`, `fa-brands`, `fa-solid`) by using the relevant class name when display the icon. For more information see [MDL-82210](https://tracker.moodle.org/browse/MDL-82210) ### Changed - The Bootstrap `.no-gutters` class is no longer used, use `.g-0` instead. For more information see [MDL-81818](https://tracker.moodle.org/browse/MDL-81818) - The `.page-header-headings` CSS class now has a background colour applied to the maintenance and secure layouts. You may need to override this class in your maintenance and secure layouts if both of the following are true: - Your theme plugin inherits from `theme_boost` and uses this CSS class - Your theme plugin applies a different styling for the page header for the maintenance and secure layouts. For more information see [MDL-83047](https://tracker.moodle.org/browse/MDL-83047)