Early in the Xfce 4.12 development cycle there was talk of being ported to GTK3, but in the end, it will still be GTK2-based. GTK+2 is the default for Xfce 4.12 but there will be partial support for GTK+3 with Xf* programs being optionally allowed to support GTK3 in parallel (libxfce4ui already supports an optional parallel GTK3 install).
Some of the features that have been completed for Xfce 4.12 include:
- Xfce's Thunar file manager finally supports tabs.
- Thunar now also has support for multiple file properties, inverting the selection, improves volume / remote location handling, and improvements to the shortcuts side pane.
- The xfce4-panel has improvements to its clock plug-in, including a popup calendar and support for timezones.
- The xfce4-settings area has improved display settings with the ability to clone displays via the GUI and other basic monitor management options. There's also now mouse settings as part of xfce4-settings.
- The xfwm4 window manager has smart placement optimizations for determining the best area to place a new window where it's least covered on the screen. Xfwm4 also now supports alinging windows next to each other rather than using random gaps.
More details on Xfce 4.12 can be found via the Wiki release engineering area. Unfortunately there's still no word on when the Xfce 4.12 release will actually happen beyond "we're still in the development stage and will start releasing when we think 4.12 is ready."