?? that looks like that bug from 23.11.18! /var/www/pioreactorui/static/exports/ should exist in newer versions - I thought I addressed that! Anyways this is the fix: New Pioreactor release: 23.11.18 - #2 by CamDavidsonPilon
I’ll think about why this happened and how to prevent it permanently.
Ack, I reintroduced this bug… 
fixed for future releases.