I had the same issue on Ubuntu 16.04 but found that apt wouldn't upgrade to the latest version of libnss3 by default.

I had to do the following:

1. Open 'Software Updater', then click on 'settings' button
2. Tick the 'important Security Updates (xenial-security) then close. it will update the cache
3. Open terminal and then run the command 'sudo apt-get install libnss3'

Should then work

I had the same issue on Ubuntu 16.04 but found that apt wouldn't upgrade to the latest version of `libnss3 by default.

I had to do the following:

-

Open 'Software Updater', then click on 'settings' button

-

Tick the 'important Security Updates (xenial-security) then close. it will update the cache

-

Open terminal and then run the command sudo apt-get install libnss3

Should then work