part of desktop background image on top of gnome-panel

[Savvas Radevic]

Binary package hint: gnome-panel

A part of desktop background image is shown on top of gnome-panel. It disappears either by clicking on the ubuntu menu item or by hovering (mouse-over) over it.
I'm not 100% sure this is a gnome-panel bug. This problem occurs at random times per day. I noticed it after upgrading to ubuntu 11.04. I use ubuntu classic with theme ambiance if it matters.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: gnome-panel 1:2.32.1-0ubuntu6.5
ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Sun Jun 12 23:09:21 2011
EcryptfsInUse: Yes
GConfNonDefault:
 /apps/panel/general/applet_id_list=[fast_user_switch_screen0,trashapplet_screen0,workspace_switcher_screen0,window_list_screen0,show_desktop_button_screen0,indicator_applet_screen0,clock_screen0,applet_1,applet_2]
 /apps/panel/general/object_id_list=[menu_bar_screen0,object_2,object_4,object_1,object_6,object_7,object_3,object_0,object_9,object_5]
 /apps/panel/general/toplevel_id_list=[bottom_panel_screen0,top_panel_screen0]
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Alpha amd64 (20100329)
ProcEnviron:
 LANGUAGE=en_GB:en
 LANG=en_GB.utf8
 SHELL=/bin/bash
SourcePackage: gnome-panel
UpgradeStatus: Upgraded to natty on 2011-05-05 (38 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Bob Bib (bobbib)]

I've noticed this bug when using Ubuntu 11.04 (amd64) with classic GNOME desktop on two machines.
One machine has nVidia GTS graphics card (with proprietary drivers installed, still running 11.04), the other has Intel GMA graphics chip (but now it's upgraded to 11.10).

From time to time some random parts (don't matter if middle, edge or center, even the main menu part became affected) of top and bottom panels spontaneously became "transparent", so the desktop background became visible through these "holes".
The affected part "heals itself" by forcing it to redraw (covering it with other graphic object, switching to the other virtual terminal and returning back etc.).

Fortunately, I haven't noticed this strange bug in 11.10.

[Alexey Baskinov (alexey-baskinov)]

The same bug occurs on a machine running Linux Mint with Gnome and the Ambance theme. "killall gnome-panel" helps to solve the problem. The computer uses ATI Mobility Radion HD 3400 and a proprietary driver FGLRX for ATI/AMD cards suggested by the driver utility.

[Bob Bib (bobbib)]

alexey-baskinov, isn't "killall gnome-panel" too violent as for temporary help? :)
Doesn't virtual terminal switching (e. g., Ctrl+Alt+F1 and then Ctrl+Alt+F7) help for you?

[Bob Bib (bobbib)]

2) another option that should work for recovering the panels is "gnome-panel --replace &"
3) someone should try another desktop theme (can Ambiance theme be buggy? everything happens! :)
4) with all these graphics cards it doesn't look like a specific graphics card driver bug

[Alexey Baskinov (alexey-baskinov)]

@ bobbib: maybe it is, I'm not experienced enough. :) I just found the solution made sure it worked for me and started using it and was happy with it until I got your message. :) Virtual terminal switching worked fine, thanks. Going to test "gnome-pannel --replace &".

[Bob Bib (bobbib)]

alexey-baskinov, "gnome-pannel --replace &" is the official way of reloading the panel when it disappears, loses applets etc.
It's not as violent as killing that process, but still is an overkill when all is needed is to redraw the panel itself.

Thus, VT switching seems to be the best workaround as for now.
Let's wait for the real bugfix ideas...

[Bob Bib (bobbib)]

// "gnome-panel --replace &" is written with single 'n', sorry.
// Unfortunately, comments cannot be edited, but it makes you think before you type :)

[Bob Bib (bobbib)]

bizhunting has written in the comment to duplicate bug #846086 that sometimes it tears not only the panels, but applications (like GIMP) too.

If I remember correctly, I've seen Firefox window corrupted few times, possibly caused by this bug.

[Alexey Baskinov (alexey-baskinov)]

Since it’s been mentioned, I have noticed that fragments of Firefox context menus sometimes disappear (Linux Mint Katya, Firefox 7.0.1).

Sometimes a part of the bottom panel disappears when a Firefox context menu is opened. An interesting instance of the bug occurred while I was writing this. I opened Firefox's context menu and a fragment of the workspace switcher disappeared and reappeared only after I closed a Nautilus window from the window list applet on the bottom panel.

@ bobbib: as promised, I tested «gnome-panel --replace &». In my case it also works fine. Thanks.

[Alexey Baskinov (alexey-baskinov)]

No statistics, unfortunately, but I think it's a Firefox related problem. My impression is that of all the applications I use (here are some of them: Keepassx, Xmind, Quanta plus, GIMP, Gedit, LibreOffice Writer, Poedit, Filezilla) only Firefox has caused memorable bug occurrences. :-) Will keep an eye on the situation.

Further to my previous message:
1. the missing fragment of the workspace switcher was NOT under just closed context menu — it was far away from it;
2. the bottom panel redrawing also takes place if a new item appears in the workspace switcher.

[Alexey Baskinov (alexey-baskinov)]

A correction of the second item of the list in the previous message: …if a new item appears in the WINDOW LIST APPLET.

[Bob Bib (bobbib)]

Bug #786973 is possible duplicate, but it needs more details.
---
> I opened Firefox's context menu and a fragment of the workspace switcher disappeared and reappeared only after I closed a Nautilus window from the window list applet on the bottom panel.

Hasn't VT switching helped?..
---
Well, as it affects not only panels, but also applications, the bug description should be slightly updated.

[Alexey Baskinov (alexey-baskinov)]

On-screen notification (IM, mail, media-player events) “deleted” a part of Skype window's main area making the desktop background visible. There was a similar issue with some other application, unfortunately I can't remember which one. Maybe that's some different bug, but I feel it is somehow related to the aforementioned.

@ bobbib: the bug reoccurred and VT switching helped.