The Plone's features page stipulates in the "Authentication and Single Sign On" section:
Easy integration with LDAP, Active Directory, Oracle, OpenID, Shibboleth, CAS, Kerberos and many other authentication systems. You name it, Plone talks to it.
But I couldn't find any information about CAS. How could use it with a Plone 5.2 site?
There are lots of CAS plugins for Plone out here. I wrote one myself long time ago. Though for Plone 5.1 https://pypi.org/project/ftw.casauth/ looks like a good shot.
Nice, thanks! I do wonder, however, whether it would work with a Plone 5.2/python3 site...
I try to make my own CAS client for Plone 4 on Python 2. I will try to support Python 3 also, but I didn't release it yet.
I want to share the information about CAS client for Plone.
Many thanks for the information: I'm watching your repository.