I recently setup SOGo to use CAS authentication against a lemonldap server.
It works but after a while (5 minutes or less, it doesn't matter if I'm actively using SOGO or it's inactive), if I try to click on, e.g., a different mail folder there's an "Unauthotized" popup.

Looking at the developer console, I see that after clicking there's a POST issued by angular.min.js, the reply is a 302 redirecting to the cas portal.
Then there's an OPTION to that url and a GET to the same url, which fails with 401 and the json content is result:0 and error:"9".
The "funny" thing is that if I copy that url and open it in a new tab, then SOGo works again for a while (though it creates a new session in sogo_session_folders).

The difference between both requests is that the request made by angular.min.js is missing the "lemonldap" cookie, while, if I paste the url in a different tab, the cookie is there.

I already changed the c_value field type of table sogo_session_folders to text (though I don't see the c_lastseen field changing when I click on different things in the sogo interface, I only see it change when I get the "Unauthorized" popup, maybe that's the problem?)