/usr/bin/pkexec:5:choose_identity:polkit_agent_text_listener_initiate_authentication:auth_agent_handle_begin_authentication:auth_agent_handle_method_call:call_in_idle_cb

The Ubuntu Error Tracker has been receiving reports about a problem regarding policykit-1. This problem was most recently seen with package version 0.105-14.1, the problem page at https://errors.ubuntu.com/problem/da61054648d6539774d46b1650c71096ced51621 contains more details, including versions of packages affected, stacktrace or traceback, and individual crash reports.
If you do not have access to the Ubuntu Error Tracker you can request it at http://forms.canonical.com/reports/.