Alt-tab causes keyboard lockup

[Bomber Cheng]

Binary package hint: compiz

Procedure to reproduce:
turn on Desktop effect
open firefox
open gnome-terminal
type some words in gnome-terminal
alt tab to firefox, alt tab back to gnome-terminal (do it quickly, may required to do it several times)
unable to type in gnome-terminal (need to resize or drag window)

no problem if Desktop effect is off

Description: Ubuntu 8.04.1
Release: 8.04
nvidia 8600GT
firefox 3.0.1+build1+nobinonly-0ubuntu0.8.04.2
gnome-panel 1:2.22.2-0ubuntu1
compiz 1:0.7.4-0ubuntu7
nvidia-glx-new 169.12+2.6.24.13-19.45

[Alexey Kotlyarov (koterpillar)]

This is actually affecting a lot of other applications. See http://ubuntuforums.org/showthread.php?t=836370
In particular: OpenOffice, Pidgin, Skype - and a lot more. Somehow Firefox seems to be an exception (it works). This renders Alt-Tab unusable, as I have to switch windows manually with mouse.

[Alexey Kotlyarov (koterpillar)]

Another observation. This does NOT happens with non-Gnome applications like xedit. KDE is affected however.

[Bomber Cheng (tomcheng76)]

Upgraded to Ubuntu 8.10 AMD64.
The problem still exists.
Can someone confirm this bug?
Firefox 3 should be the root of cause; If there is no instance of firefox3 running, alt + tab wouldn't make any problem.

[Alexey Kotlyarov (koterpillar)]

Yes, Firefox seems to be the difference.

[Alexey Kotlyarov (koterpillar)]

Seems that this is an issue of SCIM configuration:
http://sourceforge.net/tracker/?func=detail&aid=2531066&group_id=108454&atid=650539
Indeed, killing all SCIM processes stops this behavior.
Changing GTK_IM_MODULE from 'xim' as it was for me to 'scim-bridge' with
im-switch -s scim-bridge
made the issue disappear.

[Rolf Leggewie (r0lf)]

Thank you for reporting. I think this may be fixed in 1.4.9 which is about to be released in Karmic. I don't see it anymore. Please verify.

https://launchpad.net/~r0lf/+archive/hardy/+sourcepub/678492/+listing-archive-extra

[ilios (ilios86)]

The problem still exists in Ubuntu 9.10 - the Karmic Koala.
Changing GTK_IM_MODULE to scim-bridge also doesn't work.

I'm using SCIM version 1.4.9.

The following is output of command "im-switch -l"
:
ilios@ilios-server:~$ im-switch -l
Your input method setup under ko_KR locale as below.
=======================================================
The configuration "/home/ilios/.xinput.d/ko_KR" is defined as a link pointing to
scim-bridge
This private configuration supersedes the system wide default.
=======================================================
The system wide default is pointed by "/etc/alternatives/xinput-ko_KR" .
xinput-ko_KR - auto mode
 link currently points to ibus
ibus - priority 60
scim - priority 50
scim-bridge - priority 60
scim-immodule - priority 0
Current `best' version is ibus.
=======================================================
The available input method configuration files are:
default default-xim ibus nabi none scim scim-bridge scim-immodule th-xim
=======================================================

[Renee Zander (renee-zander-deactivatedaccount)]

I expierienced the same problems when using Firefox and OpenOffice at the same time several times on both of my computers.

Still exists in Karmic 9.10
Compiz enabled
Using scim for japanese typing (related?)

[Mingming Ren (portis25)]

I'm using IBUS and compiz, and I get the same problem.

But when I change compiz to gnome-shell, everything's fine.

[Nev Delap (nevdelap)]

Hi. I have this problem in 10.10. No FireFox, SCIM 1.4.9, installed from maverick repos.

Alt+tab between Gnome Terminals is fine.

Alt+tab between a Gnome Terminal and Gedit locks up the terminal every time. Alt+Tab between a Terminal and Chrome likewise. This has been the case across reboots over the two days since I installed scim.

Yesterday I had Chrome and Gedit lock up Alt+tab-ing to them, though I can't make it do that right now.

My machine with 9.10 and scim doesn't have the problem.

[Nev Delap (nevdelap)]

Ah, switching to scim-bridge is indeed the workaround.

[Kilian Evang (kevang)]

After switching to scim-bridge, I suffer only occasional lockups that are remedied by quickly alt-tabbing twice. Still very annoying.

[Rolf Leggewie (r0lf)]

For those affected in the past, has this gotten any better with the latest upstream work?

[Rolf Leggewie (r0lf)]

Closing as fix released