Deleting an action that references another action will result in the Noah ES Client crashing, the Noah ES user will be suddenly logged out and have to log in again.
The issue will not happen if you delete a single action (e.g. an audiogram).
This is most likely to happen if an HCP tries to delete a fitting and that fitting references an audiogram.
This issue will be resolved in a future Noah ES release and when the update is applied it will be noted on this page.
For now, it is not possible to delete referenced actions from the Noah ES session browser.