Thunderbird - Change Calendar time from military time

On Manjaro, I've run into an issue whre thunderbird seems to insist on using military time for the caledar scheduling. This is driving me crazy as the older I get the less I want to do math in my head.

To fix this simply open Thunderbird and go to Edit>Settings>Config Editor

From there create the following string and add the string value.

intl.date_time.pattern_override.time_short = h:mm a

Restart Thunderbird and Calendar entries should now be in standard time.