Bug 708658

Actually, there are three files in /etc/xdg/autostart which use this construct:

$ grep 'GNOME3 if' /etc/xdg/autostart/*
/etc/xdg/autostart/bluetooth-applet.desktop:AutostartCondition=GNOME3 if-session gnome-fallback
/etc/xdg/autostart/gnome-fallback-mount-helper.desktop:AutostartCondition=GNOME3 if-session gnome-fallback
/etc/xdg/autostart/gnome-sound-applet.desktop:AutostartCondition=GNOME3 if-session gnome-fallback

I don't know if the gnome-fallback-mount-helper is useful in compiz/AWN.  I've never seen it do anything when it's enabled.

IMHO, the AutostartCondition is totally broken if you're not using GNOME3.  It overrides the manual X-GNOME-Autostart flags, so it must be commented out to manually control these applets with gnome-session-properties.  Most bugs from other systems recommend copying the bluetooth and sound applet files to ~/.config/autostart and commenting the line out.  If AutostartCondition was a list like the OnlyShowIn construct, it could be written as "GNOME; GNOME3 if-session gnome-fallback;".  Another fix would be to let the X-GNOME-Autostart flags override it.

Gene

This bug is alive and well in Fedora 16 with gnome-session-3.2.1-2.fc16 and this is gnome-session which is responsible for handling that condition.  That despite that a package changelog contains these lines:

* Mon Feb 28 2011 Matthias Clasen <mclasen> 2.91.90-5
- Make the new if-session Autostart condition work

It does not work.  I cannot check rawhide as there gnome-session is currently entirely broken and does not start.

Apart of three files from /etc/xdg/autostart/ mentioned in comment #1 there is also one from gnome-session.  Namely /usr/share/gnome/autostart/gnome-authentication-agent.desktop which includes lines:

Exec=/usr/libexec/polkit-gnome-authentication-agent-1
AutostartCondition=GNOME3 if-session gnome-fallback

That is not running as well.  How to check if "gnome-fallback" key is a correct one?

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