LANGUAGE=C sudo apt-get install --reinstall flashplugin-installer 
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following package was automatically installed and is no longer required:
  libkf5kdcraw5
Use 'sudo apt autoremove' to remove it.
0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 1 not upgraded.
Need to get 0 B/6774 B of archives.
After this operation, 0 B of additional disk space will be used.
Preconfiguring packages ...
(Reading database ... 254738 files and directories currently installed.)
Preparing to unpack .../flashplugin-installer_11.2.202.577ubuntu1_amd64.deb ...
Unpacking flashplugin-installer (11.2.202.577ubuntu1) over (11.2.202.577ubuntu1) ...
Processing triggers for update-notifier-common (3.166) ...
flashplugin-installer: downloading http://archive.canonical.com/pool/partner/a/adobe-flashplugin/adobe-flashplugin_20160310.1.orig.tar.gz
Get:1 http://archive.canonical.com/pool/partner/a/adobe-flashplugin/adobe-flashplugin_20160310.1.orig.tar.gz [27,0 MB]
Fetched 27,0 MB in 3s (8319 kB/s)                                                                                           
W: Can't drop privileges for downloading as file '/var/lib/update-notifier/package-data-downloads/partial/adobe-flashplugin_20160310.1.orig.tar.gz' couldn't be accessed by user '_apt'. - pkgAcquire::Run (13: Permission denied)
Installing from local file /var/lib/update-notifier/package-data-downloads/partial/adobe-flashplugin_20160310.1.orig.tar.gz
Flash Plugin installed.
Setting up flashplugin-installer (11.2.202.577ubuntu1) ...