I bug tested this for many days. Found out plugins where causing hiccups. Trailers, Cinema-mode, Tunein and TV Mosaic (same with DVB Logic). Caused infinite loading and library not showing in home screen. I also reverted to older versions of server until I had the same problems when testing with plugins. Deleting the plugins above made server fast as ever especially on latest version and also bug free. Encounter the library not showing up again after installing TV Mosaic. Livet works as it should but library with movies and tv series is somehow gone and not working. (Uninstall TV Mosaic and library is back)I have had a lot of problems with Emby server for macOS lately. First of I managed to find out that the Trailers plugin which is installed as default makes the library disappear and causes infinite loading times when trying to access the server. Cinema-mode I have never gotten to work stable before and can also point out this plugin as a unstable interference for the server. I also found out that the Tune-in plugin causes the same problem although I do not have a user so this might work with premium subscription. But I don't think it should cause these problems without giving any info that the lack of login might cause these issues.
As the latest hiccup I have set up TV Mosaic as a backend for Live TV that I finally got working perfectly with IPTV as source. But when I install and set up in Emby server. Movie and TV Library disappears (like the earlier problems described above) and an infinite loading symbol circles the screen. In the menu there is no Movie or tv marking anymore. So the only difference from before is that live-tv works and shows up when accessing Emby. Uninstalling TV Mosaic reverts the problem and server is normal again. I have also tried with the DVBLink plugin to no avail (I assume the code is identical even so). I also tried to install an earlier version of TV Mosaic to no avail. IPTV and EPG source works, but it is just too messy and too slow to try to sort and configure the live-tv and channel setup in Emby.
I will probably research exporting m3u streams from tv mosaic for now but if anyone has some solutions or feedback I would very much appreciate the help.
Thought it would be good to share my experience and research no matter what.