We have many dashboards used by our (external) customers.
Each client can see their own dashboard and cannot see all other dashboards.
This works pretty well, but we want to organize dashboards into folders and we don't want customers to be able to see the folder they don't have a dashboard in.
I don't see how to apply the folder access list like it's possible on dashboards.
Full access (test folder and test dashboard are visible):
Restricted access (no dashboard test is visible, but folder test is visible):
I believe there is already a similar question:
Checking the task referenced in the answer, this has not been implemented yet.
There is also a feature suggestion related to this feature