Ubuntu 11.10 (i386, amd64)
unity-greeter 0.1.1-0ubuntu1
1) Leaded purely by curiosity, I launched unity-greeter (/usr/sbin/unity-greeter) from the GNOME terminal while in GNOME 3 fallback mode.
This opened smth. like LightDM login screen in a window and smashed the desktop UI theme: the top and bottom GNOME panels and window backgrounds went grey, the icons went old-style (but window title bars style is not ruined).
I closed that window and killed unity-greeter with Ctrl+C, but that unpleasant visual effects still remain and cannot be fixed by changing the theme in gnome-control-center or gnome-tweak-tool. Rebooting has no effects.
One more unpleasant effect: keyboard layout switching icon has disappeared, so layout switching shortcuts don't work, therfore i need to use setxkbmap.
Finally, radically fixed these symptoms by removing the ~/.config/dconf/user file and then reconfiguring the needed desktop options from scratch.
2) Tried to launch the unity greeter while in GNOME 3 Shell session. After playing with the window (I tried to scroll the user list), it had the same effect. One time though the mouse cursor got nailed at the center of the screen, so I needed to press Ctrl+Alt+Del to open log out dialog.
3) Unity also can be ruined this way. I tried this in Ubuntu 11.10 LiveCD. unity-greeter is launched the same way and after some window dragging the theme gets corrupted and gnome-settings-daemon crash error window appears (apport reports are registered as bug #878874 for i386 and as bug #876752 for amd64).
It can be just a gnome-settings-daemon bug triggered by unity-greeter, but I'm not sure.
This bug was fixed in the package unity-greeter - 0.2.0-0ubuntu1
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unity-greeter (0.2.0-0ubuntu1) precise; urgency=low
* New upstream release
- Improve scrolling animation (LP: #844050)
- Select menubar when F10 is pressed
- Fix Orca not starting when enabling screen reader (LP: #850554)
- Add a keyboard indicator (LP: #783827, LP: #834487)
- Always focus new windows
- Check version of Vala when compiling
- Update logo for 12.04 (LP: #892394)
- Use default invisible character in password dialog (LP: #834878)
- Darken indicator bar
- User smaller grid size
- Put end-stops on user list scrolling
- Only fade out user labels that can't fit in completely (LP: #883260)
- Center dots (LP: #872800)
- Add translator comments (LP: #855385)
- Add option to disable dots (LP: #883908)
- Only redraw parts of the screen that have changed
- Don't run the greeter if can't connect to daemon and not in test mode
(LP: #876754)
-- Robert Ancell <email address hidden> Thu, 19 Jan 2012 14:56:21 +1100