Gnome-shell freezes when running looking glass

[Cefn]

I was aiming to do some work to bring this critical extension back into a functioning state against 3.8...
https://github.com/csoriano89/Extensions-enhance-overview/issues/3

Invoking Alt+F2 lg to launch looking glass offers a semi-transparent overlay and a script interpreter which is superficially functional (if you don't move your mouse around) I can get a report of window actors for example, by following the Gnome-shell debugging walkthrough.

However, if I move the mouse over the top bar of the looking glass application, the whole of Gnome-shell freezes and needs to be relaunched in order to get any interactivity back. X clients are still operational after an CTRL+ALT+F1 and kill and restart of gnome-shell on DISPLAY=:0

Attached is the standard error from gnome-shell which results from replicating the issue deliberately (after an initial restart of gnome-shell).

In the meantime, given I can't fix the extension, is there any way at all that I can filter the overview to show windows which belong to a specific application. This is a critical capability for modern desktops, where in my case I can have 15 or so browser windows and the same number of Evince windows when doing research. Without filtering, as provided by Unity and Expose, it's essentially impossible to navigate the desktop.

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: gnome-shell 3.8.4-0ubuntu1
Uname: Linux 3.11.0-031100rc6-generic i686
ApportVersion: 2.12.1-0ubuntu3
Architecture: i386
Date: Wed Sep 4 11:27:27 2013
DisplayManager: gdm
GsettingsChanges:
 b'org.gnome.desktop.interface' b'clock-show-date' b'true'
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'"
InstallationDate: Installed on 2013-08-15 (19 days ago)
InstallationMedia: Ubuntu-GNOME 13.10 "Saucy Salamander" - Alpha i386 (20130626)
MarkForUpload: True
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)

[Jeremy Bícha (jbicha)]

Thank you for reporting this bug to Ubuntu. I apologize that we are not always to respond to bug reports promptly. Ubuntu 13.10 reached End of Life in 2014. See this document for currently supported Ubuntu releases: https://wiki.ubuntu.com/Releases

Please upgrade to Ubuntu 16.04 LTS and re-test. If the bug is still reproducible, increase the verbosity of the steps to recreate it so we can try again.

Do feel free to report any other bugs you may find.