$ sudo apt install --reinstall flashplugin-installer
Reading package lists... Done
Building dependency tree       
Reading state information... Done
0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 0 not upgraded.
Need to get 7 018 B of archives.
After this operation, 0 B of additional disk space will be used.
Get:1 http://archive.ubuntu.com/ubuntu yakkety/multiverse amd64 flashplugin-installer amd64 11.2.202.616ubuntu5 [7 018 B]
Fetched 7 018 B in 0s (82,8 kB/s)                 
Preconfiguring packages ...
(Reading database ... 305484 files and directories currently installed.)
Preparing to unpack .../flashplugin-installer_11.2.202.616ubuntu5_amd64.deb ...
Unpacking flashplugin-installer (11.2.202.616ubuntu5) over (11.2.202.616ubuntu5) ...
Processing triggers for update-notifier-common (3.168) ...
flashplugin-installer: downloading http://archive.canonical.com/pool/partner/a/adobe-flashplugin/adobe-flashplugin_20160407.1.orig.tar.gz
Get:1 http://archive.canonical.com/pool/partner/a/adobe-flashplugin/adobe-flashplugin_20160407.1.orig.tar.gz [27,0 MB]
Fetched 27,0 MB in 9s (2 887 kB/s)                                                                                                              
W: Can't drop privileges for downloading as file '/var/lib/update-notifier/package-data-downloads/partial/adobe-flashplugin_20160407.1.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_20160407.1.orig.tar.gz
Flash Plugin installed.
Setting up flashplugin-installer (11.2.202.616ubuntu5) ...