window switcher stuck (not only, but can be triggered with Onboard)

[Anders Feder]

When report was generated, the Alt+Tab task switcher was stuck. I could access all interface elements as I normally would, but the task switcher was stuck in the foreground of everything and would not hide and open the selected application window as it should.

I don't know how to reproduce the issue, but are reporting it for the record.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: unity 4.8.2-0ubuntu4
ProcVersionSignature: Ubuntu 3.0.0-9.12-generic 3.0.3
Uname: Linux 3.0.0-9-generic x86_64
Architecture: amd64
CompizPlugins: [core,bailer,detection,composite,opengl,decor,mousepoll,vpswitch,regex,animation,snap,expo,move,compiztoolbox,place,grid,imgpng,gnomecompat,wall,ezoom,workarounds,resize,fade,unitymtgrabhandles,scale,session,unityshell]
Date: Tue Aug 23 15:56:51 2011
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64 (20110427.1)
ProcEnviron:
 LANGUAGE=da:en
 PATH=(custom, no user)
 LANG=da_DK.UTF-8
 LC_MESSAGES=da_DK.UTF-8
 SHELL=/bin/bash
SourcePackage: unity
UpgradeStatus: Upgraded to oneiric on 2011-08-20 (3 days ago)

[Lê Hoàng Phương (herophuong93)]

I can confirm that. It sometimes stuck but I also don't know how to reproduce it.

[Lê Hoàng Phương (herophuong93)]

I have attempted to reproduce that. This is one way:
1. Open empathy chat window
2. Input text with *ibus* *enabled*
3. Send text by press enter
4. Using Alt + Tab when the cursor is *still* inside textbox
-> Result: Task switcher is stuck on the foreground.

[Lê Hoàng Phương (herophuong93)]

Another way: Using Alt+Tab by Onboard (The default onscreen keyboard in Oneiric).

[Omer Akram (om26er)]

I confirmed with alt-tab through Onboard.

[Anders Feder (afeder)]

Yet another way:

1. Open a terminal.
2. Run the command 'xprop'.
3. Press Alt-Tab.
4. The task switcher is stuck.

[David Barth (dbarth)]

It also happened for me without onboard or xprop, just by pressing alt-tab and then doing "something" that the switcher didn't like.

Attached is the output of xininfo -root -tree when this happened.

[David Barth (dbarth)]

It seems like a serious usability issue, in that youcan barely use your system once the switcher is stuck.
Raising the priority and nominating to the weekly milestone list for consideration.

[Jason Smith (jassmith)]

This fix is in for the case other than onboard. Onboard unfortunately is a case where you can't unselect the "alt" so alt-tab thinks you are still holding the key. This is out of scope for the bug.

[Launchpad Janitor (janitor)]

This bug was fixed in the package unity - 4.16.0-0ubuntu1

---------------
unity (4.16.0-0ubuntu1) oneiric; urgency=low

  * New upstream release.
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    ...