GTK and GNOME are closely related. Considering that GNOME 3.34 (beta 2 now available) will be released on September 11 and that it is more than likely to be included in Eoan Ermine, many of us would have hoped or wished that gtk4 It will arrive at Ubuntu 19.10, but it will not be like that. In fact, it is not easy to get to Ubuntu 20.10, since it is already known that the next version of the formerly known as GIMP Toolkit will not arrive until fall 2020.
It will be then when the Ubuntu 20.10 G releases coincide. GAnimal, GNOME 3.38 and GTK 4 target. announced recently at the annual GNOME GUADEC conference, where they also advanced some of the news that will come with that version, such as new additional metadata to topic index files to indicate "dark mode" topics, among others dark mode improvements.
Some confirmed news of GTK 4
- New additional metadata to theme index files to indicate "dark mode" themes, among other dark mode enhancements.
- Added a scalable list view widget to GTK4 that recycles row widgets.
- The infrastructure and APIs around animations in GTK4, similar to how animations behave in CSS.
- The menu / popover rework for GTK 4.0 is expected to be finalized.
- Using event handlers for shortcuts to replace mnemonics / accelerators / keybindings.
- Completed the new drag and drop API.
- Some of the non-blocking features covered are a widget repository, a UI layout widget, and better support for split header bars and state transitions.
Before the official release of GTK 4, they are preparing the release of GTK 3.99 before the end of 2019. The intention is that this version will be ready to be used together with GNOME 3.36 and that GTK 4 will do the same with GNOME 3.38.