Problem: When connecting to a pfsense firewall webConfigurator (admin page) configured to use Let's Encrypt certificates you find the certificate is expired.

Cause: The webConfigurator site was not restared when the certificate was renewed

Resolution: Configure the webConfigurator site to auto-restarted when the certificate is updated

Goto Services => Acme Certificates

Select to edit the cert you are using for the webConfigurator

At the bottom of the Certificates tab in the Actions list section click Add

Command: /etc/rc.restart_webgui

Method: Shell Command

To view where each certificate is being used Goto System => Cert. Manager => Certificates