Reporting as a bug per recommendation from Ironic_8b49#9887 on Discord.

When messages in lang.yml are set to '', the expected behaviour is that no messages of that type will be sent in chat at all. Instead, blank one line messages are sent. In the screenshot below, location-requirement, time-requirement, and successfully-completed-requirement are all set to '' in lang.yml. The path requires ten minutes of playtime and for the player to be in a certain location. "Congration, you done it!" is the message to be shown when the path is complete.