Deprecation of /usr/share/applications/defaults.list and how to handle default applications across desktops

[Olav Vitters <olav vitters nl>]

Hello,

Please note that around April 2014 the following freedesktop.org changes
happened:
1. Session .desktop files should contain a list of desktops, e.g.
   DesktopNames=GNOME-Classic;GNOME
2. Display Managers are expected to set $XDG_CURRENT_DESKTOP
   Using DesktopNames. Done by at least GDM 3.14, KDM, SDDM
3. Deprecation of "glib" /usr/share/applications/defaults.list
4. Introduction of /usr/share/applications/$desktop-mimeapps.list
5. KDE and GNOME 3.14+ will still ensure XDG_CURRENT_DESKTOP is set
   See startkde, gnome-session. Latter doesn't override if already set.

Please perform the following in your distribution:
A. If your distribution currently ships a defaults.list file, please
   rename it to e.g. gnome-mimeapps.list (lowercase!).
B. Check that the non-GNOME,non-KDE session desktop files (Cinnamon and
   so) contain something such as:
     DesktopNames=Cinnamon;GNOME
C. Verify that e.g. the gnome.desktop session file actually contains
   DesktopNames.
   This has done within GNOME, but at least one distribution uses a setup
   whereby these desktop files get overwritten/recreated without that
   key so best to check the key is there.
D. If your distribution uses display managers other than GDM, KDM, SDDM
   verify that these set $XDG_CURRENT_DESKTOP
   There's still a fallback within gnome-session and startkde, so this
   is for other desktops.

For more details please see
http://standards.freedesktop.org/mime-apps-spec/mime-apps-spec-latest.html
-- 
Regards,
Olav