/usr/lib/x86_64-linux-gnu/indicator-messages/indicator-messages-service:11:ACT_IS_USER:_act_user_update_from_object_path:fetch_user_incrementally:on_find_user_by_name_finished:g_task_return_now

The Ubuntu Error Tracker has been receiving reports about a problem regarding indicator-messages. This problem was most recently seen with package version 13.10.1+18.10.20180918-0ubuntu3, the problem page at https://errors.ubuntu.com/problem/2416b63fd3efcd8ec09f184b6f50981fc56fb16d 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 and are a software developer, you can request it at http://forms.canonical.com/reports/.