I am using Grav with Plugin Flex-Objects installed just for Admin.
When I try to go to Admin > Accounts > Configuration (TAB) I get an error.
in line 244:
Return value of Grav\Framework\Flex\FlexDirectory::loadDirectoryConfig() must be of the type array, null returned
I have tested it with user Admin rights and 2 seperate installations.
Grav, Admin and Flex-objects are up to date.