This function is only available on those folders for which the user has more than consumer rights.
Clicking "Folder Permissions" on the folder menu, a new tab will open and display the users and group rights set on this folder. The table indicates for which user which rights are set, if the user receives the right through the group, if the rights were inherited from a parent folder and the Authority Type.

You can click on the folders in the path to see how the rights are set in the folders above. To change user settings, you have to move to the folder in the Browse tab and then click "Show in Browser" to jump to the Browser where you will be able to change the access rights.