30 answers
Thanks for everyone's help. ServiceRocket noticed we had run a Health Check under salesforce Security Controls and had turned on a clickjack protection item to increase our security health score. Since turning off the clickjack item, the error has stopped.
https://docs.servicerocket.com/salesforce-jira/getting-help/knowledge-base/url-no-longer-exists-when-trying-to-load-visualforce-pages