I find myself in a strange situation, I no longer have access to all the topics available on plex as you can see in the column, there are missing options and if I click on the library, I have an error message ‘‘server settings are unavailable’’.
To test, I uninstalled plex media server and install again, but same problem.
To test, I opened a new account with premium pass.
And I have no more problem so the problem is related to my account or settings.
Yes there is a known issue with older Macs and the 1.29.1 plex series. They are working on a fix. The solution for now is to downgrade to 1.28.2 or 1.29.0 which work still. The threads about this often have the words Settings unavailable in the topic.