Notebookbar, or tabbed interface is an attempt to modernize LibreOffice user interface. In these series, I try to explain the implementation in LibreOffice code. In the first part, I discuss custom Glade widgets that are building blocks of Notebookbar user interface. Building LibreOffice From Sources If you haven’t built LibreOffice from sources before, you can refer to can refer to this tutorial: Getting Started (Video Tutorial) The next sections assume that you have a working build enviro...