The Diagram Application 1.3 has been released.
This extension is not supported by the XWiki developers. It's being released since it had some bugfixes since 2017 that had not been released. It's recommended to use the Diagram Application (Pro) which offers new features (draw.io upgrade, SVG-based PDF export, better link management and Gliffy diagrams support) and bug fixes including blocker issue Can't import a diagram and more.