I recently installed 18.04 and am running Thunderbird 60.2.1 with Lighting 6.2.2.1. It appears the Lightning calendar is using a different time than my system time. I recently migrated to a new computer, and copied my old Thunderbird profile to the new computer. However, migrating to the new computer was done in a different time zone, but it seems Thunderbird/Lighting did not update to the required time zone. For example, I am now on east coast by the lightning time zone behaves as if it is on the west coast. If i add a new event for 2 minutes in the future and tell it to give a notification 0 minutes beforehand, it will not show a notification if I assume the time zones are correct. However, if I add the event for 3 hours in the past (my old time zone, and that of the old profile I copied) it will then show a pop-up notification for the event. So why is Lightning using a different time zone than my system time zone, and how do I change it?