Lumina 1.4.0 is a major release that introduces several new core components, such as the Lumina Theme Engine to provide enhanced theming capabilities for the desktop environment and apps written in the Qt 5 application framework. The Lumina Theme Engine comes with a configuration utility and makes the previous desktop theme system obsolete, though it’s possible to migrate your current settings to the new engine. The Lumina Theme Engine also comes with a bunch of superb wallpapers contributed by various artists (check them out in the screenshot gallery attached at the end of the article), and Lumina 1.4.0 is the first release of the desktop environment to ship with a standalone, built-in PDF viewer called lumina-pdf, which can be used to view, present, and print PDF documents.