A ribbon-style UI will be optionally available not too long from now. You can already try it out in LibreOffice 5.3 by ticking the "Enable experimental feature

A ribbon-style UI will be optionally available not too long from now. You can already try it out in LibreOffice 5.3 by ticking the "Enable experimental features (may be unstable)"-checkbox in the settings under LibreOffice->Advanced. Then in the menubar, select View->Toolbar Layout->Notebookbar.