Behörighet saknas while viewing panel

I’m getting a permission issue “Behörighet saknas” when I try to display a panel.
I can view the administration part of the panel, though.
I have set all permissions to the user.

Litium version: 6

This is a bug that is fixed in 6.2, see https://docs.litium.com/support/bugs/bug_details?id=41828