How do I get the active window on Gnome Wayland?

Question

Background: I\'m working on a piece of software called ActivityWatch that logs what you do on your computer. Basically an attempt at addressing some of the

Answer 1

The two previous answers are outdated, this is the current state of querying appnames and titles of windows in (Gnome) Wayland.

1. A Gnome-specific JavaScript API which can be accessed over DBus
2. The wlr-foreign-toplevel-management Wayland protocol (unfortunately not implemented by Gnome)

The Gnome-specific API will likely break between Gnome versions, but it works. It is heavily dependent on Gnome internal API to work so there is no chance of it becoming a standard API. There is a PR on aw-watcher-window to add this, but it needs some clean-up and afk-support if that's possible.

The wlr-foreign-toplevel-management protocol is (at the time of writing this) implemented by the Sway, Mir, Phosh and Wayfire compositors. Together with the idle.xml protocol which is pretty widely implemented by wayland compositors there's a complete implementation with afk-detection for ActivityWatch in aw-watcher-window-wayland. I've been in discussions with sway/rootston developers about whether wayland appnames and X11 wm_class is interchangeable and both Sway and Phosh use these interchangeably now so there should no longer be any distinguishable differences between Wayland and XWayland windows in the API anymore.

I have not researched if KWin has some API similar to Gnome Shell to fetch appnames and titles, but it does at least not implement wlr-foreign-toplevel-management.