There seems to be a new file format in the works to define Gnome UI with a lot of advantages:
- Concise syntax. No more clumsy XML! Blueprint is designed from the ground up to match GTK’s widget model, including templates, child types, signal handlers, and menus.
- Easy to learn. The syntax should be very familiar to most people. Take a look at the reference to get started.
- Modern tooling. Blueprint ships a Language Server for IDE integration.
Is the GNOME team plan to embrace this tool as an ‘official’ GTK tool, and replace the archaic XML format to design UIs?
Not sure, but I guess the builder will probably just work with both.