无需重登/重启：Unity会话故障及顶栏缺失的修复方法问询

Alright, I’ve fought this exact Unity issue more times than I can count—especially after running unity --reset-icons && killall -9 compiz to trigger the bug. No need to log out or reboot; here’s how to fix it step by step:

1. Restore Compiz (Window Manager) #

The hard kill on compiz is usually the root cause of the messed-up session. Open a terminal (use Ctrl+Alt+T if the top bar is gone, or switch to a TTY with Ctrl+Alt+F2, log in, then run these commands before switching back with Ctrl+Alt+F7):

• Stop any leftover compiz processes cleanly:
  killall -SIGTERM compiz
• Restart compiz properly and detach it from the terminal so it stays running:
  compiz --replace & disown

2. Bring Back the Top Bar & Unity Applets #

If the system menu top bar and applets are still missing, restart the Unity panel service:
unity-panel-service --replace & disown
This should immediately restore the top bar, including the system menu, indicators, and applets.

3. Fix Unresponsive dconf/gsettings #

Even if dconf-service is running, cached settings might be blocking changes. Reset the Compiz and Unity-related dconf entries to default:

• Reset Compiz configuration:
  dconf reset -f /org/compiz/
• Reset window manager settings:
  dconf reset -f /org/gnome/desktop/wm/
• After resetting, re-run the compiz and panel service commands from steps 1 and 2 to apply the fresh settings.

4. Bonus: Restore Unity Icons (If Needed) #

If your desktop icons are still messed up after the above steps, run:
unity --reset-icons & disown
This refreshes the icon layout without breaking the session again (just avoid hard-killing compiz right after!).

Testing the Fault Environment #

To replicate the issue for testing, use the exact command you mentioned:
unity --reset-icons && killall -9 compiz
This reliably triggers the broken session state, so you can test the fixes above.

内容的提问来源于stack exchange，提问作者ubuntroll