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apport stop/waiting
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Unpacking xul-ext-ubufox (3.1-0ubuntu0.14.04.1) over (3.0-0ubuntu0.14.04.1) ...
dpkg: warning: unable to delete old directory '/etc/xul-ext': Directory not empty
Processing triggers for ureadahead (0.100.0-16) ...
ureadahead will be reprofiled on next reboot
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(gtk-update-icon-cache-3.0:7612): GdkPixbuf-WARNING **: Cannot open pixbuf loader module file '/usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders.cache': No such file or directory

This likely means that your installation is broken.
Try running the command
  gdk-pixbuf-query-loaders > /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders.cache
to make things work again for the time being.
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Processing triggers for desktop-file-utils (0.22-1ubuntu1) ...
Processing triggers for bamfdaemon (0.5.1+14.04.20140409-0ubuntu1) ...
Rebuilding /usr/share/applications/bamf-2.index...
Processing triggers for mime-support (3.54ubuntu1.1) ...
Processing triggers for update-notifier-common (0.154.1ubuntu1) ...
flashplugin-installer: downloading http://archive.canonical.com/pool/partner/a/adobe-flashplugin/adobe-flashplugin_20150811.1.orig.tar.gz
Installing from local file /tmp/tmpk_RUkb.gz
Flash Plugin installed.
Setting up dh-apparmor (2.8.95~2430-0ubuntu5.3) ...