In the update process did not find the help files:
Migrating erpnext.vm
Updating DocTypes for frappe : [========================================]
Updating DocTypes for erpnext : [========================================]
Syncing help database…
/home/frappe/frappe-bench/apps/frappe/frappe/build.py:106: UserWarning: Source /home/frappe/frappe-bench/apps/erpnext_demo/erpnext_demo/docs does not exists.
warnings.warn(‘Source {source} does not exists.’.format(source = source))
VM VIRTUALBOX: 5.1.30
Installed Apps
ERPNext: v9.1.6 (master)
Frappe Framework: v9.1.8 (master)