The cause was a clash between Qt’s GPU detection and Calibre’s PDF parser, which both need different versions of libxml2. Papers, Ubuntu’s PDF viewer, fixed its own PDF link bug recently – must be something in the air! Calibre’s Content server UI can be installed as a web appOther fixes mainly target issues using Calibre’s content server, a nifty features that lets you brow, open and manage your ebook library from a host computer using a web browser on another, like a smartphone or tablet. Missing options when converting ebooks via the content server UI have also been restored. For Linux, Calibre is installed by running a script that downloads a binary build.