After the update using emby in everyday use it is very very slow and demotivating.
My librarysize may be huge (5 GB) and contains a mass of files with ~30 libraries.
But the new speed is totally different to 4.5.4, which was not the fastest, but for daily use ok.
I think, because everything is tag based now, each procedure requires a database requiry through the whole database.
In detail: On the start screen it is impossible to activate "show new media". I lasts minutes till