Error message "retrieving event handlers" when navigating to projects with read only "Allow All Data Access"

The following error message frequently pops up when navigating back to a project via the breadcrumb or the top ribbon for users granted read only "All Data Access"

An error occurred retrieving event handlers for this project: [error] Not Found

When their access is elevated to read and write the error message ceases. The message is harmless as it can be safely dismissed but can be a annoyance for the user.

NB: No event handlers have been configured for any project