Firefox fails to clear local storage

[Paul Crawford]

I noticed that Firefox is keeping site-specific information even after using the 'Clear Recent History' option. For example, with a new firefox profile (e.g. start a guest session) go to www.youtube.com and view some video, then look in the location:

~/.mozilla/firefox/<randome name>/storage/default/

You should see a subdirectory named "https+++www.youtube.com". Now clear all history using the menu option History -> Clear Recent History... by selecting "everything" and ticking all boxes.

Result should be no sign of having visited youtube. However the site-specific storage directory still exists which is a significant laps of privacy. It seems not to happen in a private tab, but that is not an excuse for failing to clear on requested.

$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 14.04.5 LTS
Release: 14.04
Codename: trusty

$ apt-cache policy firefox
firefox:
  Installed: 51.0.1+build2-0ubuntu0.14.04.2
  Candidate: 51.0.1+build2-0ubuntu0.14.04.2
  Version table:
 *** 51.0.1+build2-0ubuntu0.14.04.2 0
        500 http://gb.archive.ubuntu.com/ubuntu/ trusty-updates/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu/ trusty-security/main amd64 Packages
        100 /var/lib/dpkg/status
     28.0+build2-0ubuntu2 0
        500 http://gb.archive.ubuntu.com/ubuntu/ trusty/main amd64 Packages

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.