Calibre 2.80 comes two weeks after Calibre 2.79 and appears to be a major release that introduces quite a bunch of new features and new news source, besides the usual bug fixes. The most significant addition being the ability to sideload KFX files that have been created using the third-party KFX plugin for Calibre. Among other new features implemented in Calibre 2.80, we can mention the ability to drag and drop images, HTML and stylesheet files directly into the Edit Book component, allowing the insertion of relevant <link> and tags, as well as the automatic addition of these files to the book.