The lxpanel-freeze bug in Knoppix 6

[utu]

.
There is a fairly widespread bug which appears most likely to be in
lxpanel which affects a number of Linux distros, probably described
as well for all in Ubuntu Launchpad Bug 800297 at

https://bugs.launchpad.net/ubuntu/+source/lxpanel/+bug/800297

I think this bug has plagued Knoppix 6 for a long time. I get around
this bug with Control-Alt-Backspace, and don't think I have lost any
'work' in progress that I can recall.
However, I think this is an unhealthy aberration which should come
under greater scrutiny culminating in some corrective action.

There is an alternative to lxpanel called Tint2 which may not have
the problems of lxpanel which some Linuxers are trying out. See

http://code.google.com/p/tint2/

I'd be interested to know:
(1) If others on this forum have observed the lxpanel-freeze bug;
(2) If anyone has a really 'bad' experience as a result of this bug;
(3) If any of you found work-arounds or solutions to this problem; and
(4) If anyone has tried out Tint2, and if so, how did that turn out.

[kl522]

(3) If any of you found work-arounds or solutions to this problem; and


I don't really use lxpanel ( that much ). I shrunk lxpanel to 40x25 pixels which allows me to only bring up the lxpanel menu and for that I also enabled auto-hide, ie lxpanel is not shown until I bring the mouse to that corner of the window.

I use glx-dock instead :-

http://www.glx-dock.org/index.php

[utu]

Here's another look at the problem.
Not clear he's solved the problem for everybody, noting the first response.

http://hardc0l2e.wordpress.com/2011/09/05/lxpanel-freeze-after-closing-libreoffice-document/

[utu]

An alternative to control-alt-backspace
.
Control-Alt-Backspace is probably a bit heavy-handed.

Luckily, in my case this usually happens on closing a LibreOffice program,
which in itself seems always to have been successful.
Probably any small, concurrent, un-saved text programs in Leafpad may have
been sacrificed with a Control-Alt-Backspace shutdowns, and I've just not
been too excited about that, being more concerned about the survival of
larger LibreOffice works in process.

I expect trying to re-activate just lxpanel and not kill x entirely
might be a better work-around. Toward that end, the following
gnome-panel-restart approach may be worth trying:

http://mylinuxnotebook.blogspot.com/2008/09/restart-gnome-panel.html

[utu]

.
I finally had another lxpanel freeze today after closing
LibreOffice. Only pcmanfm and LO icons left on the
un-responsive lxpanel, no other programs left to close.

I remembered to try Alt+F2 and tried that and a number of
Alt-Fn and Ctl-Alt-Fn combinations and none of these worked.

I did not remember Alt-Tab, so we'll try to remember to
try that next time.

-----------
It is possible, I suppose that Compiz may also have something
to do with anomalous screen behaviour, hence the following
addendum.

FWIW, I have Compiz operative, but have Scale & Expo effects
disabled, since they annoy me with screen-edge-activation.
I am similarly annoyed at a spurious screen-cube-activate-rotation
which I've not been able to isolate as to which effect to modify.

[utu]

Status, as of 21 October 2011.

I have observed a persistent flaw in the operation of the LXDE
0.5.8-2 lxpanel function in Knoppix 6. I have commented on this in
Knoppix and LXDE forums several times previously, to no effect.
The flaw appears to apply to other LXDE distributions as well.

I have personally only observed this flaw in the context of
Knoppix 6, when using LibreOffice for some rather complex spreadsheet
operations, used always together with a browser on-line and using
some cut-and-paste data manipulations.

On closing LibreOffice after some of these spreadsheet operations,
I occasionally find that lxpanel no longer responds to mouse and/or
keyboard inputs. At such times there may remain icons on lxpanel,
representing programs including LibreOffice that were previously
in use. Also, at such times, the desktop responds to mouse right-
clicks, but the Knoppix screen for the most part responds only to
the Control-Alt-Backspace command, so far as I am able to determine.
No Alt-Tab, Ctl-Fn nor Ctl-Alt-Fn commands seem to have any effect.

A mouse right-click on the desktop space may bring up any of several
GUIs, but none of these offer any avenue to input an appropriate
corrective screen command, as far as I can tell.

I can easily reactivate lxpanel and regain mouse and keyboard
functionality with the Control-Alt-Space command with apparently
no ill effect to LibreOffice, which apparently shuts-down correctly.
I am unclear as to whether other programs, such as a text editor
still open at the shut-down of LibreOffice may have been affected.
Were it possible to do so, I would have chosen to attempt to close
all programs still open, before doing a full reset of X.

It would appear Ubuntu thinks this is an 'upstream' problem,
'affecting (only) three people', and one gets the impression the
LXDE forum is not close enough to LXDE's godfather to get any
corrective action initiated there, either.

I am open to suggestions, but Control-Alt-Backspace is the only
method of recovery of which I am aware.

[kl522]

Since this bug is only shown when you use lxde with LibreOffice, it may be LibreOffice which is bugged instead of lxpanel. In any case, you have at your disposal synaptic package manager, you might want to try different versions of lxpanel and/or LibreOffice. Downgrading the version to stable might be worth trying too. You will help the community in identifying the bug by doing so.

[Werner P. Schulz]

Do you still use the testing version of "lxpanel", or did you try to downgrade to stable version "0.5.6-1"?
I don't know why KK mixed "testing" and "stable" within the LXDE stuff.

Greetings Werner

[utu]

Greetings, Werner & kl522

I think both suggestions are very appropriate, however:

1- I don't know how to 'downgrade' something using Synaptic; and
2- I did not get a good feeling from browsing the LibreOffice site some time back
that there was any very well organized bug-repair activity there.

I recall Werner solved one lxmenu problem by downgrading, so that's surely
a possibility, but I'll need some tutoring.

[utu]

Greetings, Werner & kl522

I think both suggestions are very appropriate, however

1- I don't know how to 'downgrade' something using Synaptic; and
2- I did not get a good feeling from browsing the LibreOffice site some time back
that there was any very well organized bug-repair activity there.

I recall Werner solved one lxmenu problem by downgrading, so that's surely
a possibility, but I'll need some tutoring.

Update: I just found 'Force Version' and am trying the 'stable' lxpanel offering.
Now, we'll have to wait for another upset to see how things progress.

Thanks, again.

[utu]

Since this bug is only shown when you use lxde with LibreOffice,
it may be LibreOffice which is bugged instead of lxpanel.@ kl522

I agree that the problem may just as likely be in LibreOffice as in LXDE, but
if you go to the LO forum, you find this problem is declared 'SOLVED' there,
by replacing lxpanel with something else.

http://en.libreofficeforum.org/node/834

I take this to mean there won't be any further examination of how
LibreOffice itself might be adjusted to get around the problem.

Also, I don't think I see a 'Force Version' alternative for LibreOffice as
I found for lxpanel. That is, a way to roll-back to an earlier version.

[utu]

The roll-back of lxpanel does NOT solve my problem.

[utu]

It's possible that Mandriva has a handle on this.

http://pkgs.org/mandriva-2011/mandriva- ... #changelog (http://pkgs.org/mandriva-2011/mandriva-main-testing-i586/lxpanel-0.5.8-4-mdv2011.0.i586.rpm.html#changelog)

[utu]

.
KK has brought this Mandriva fork solution to Debian in lxpanel 0.5.8-3-debian-knoppix
now in the (debian-knoppix.alioth.debian.org) repository.