Emby’s web client is built on React (and potentially other modern frameworks), resulting in obscure CSS class names (e.g., class="itemTile-3xYz" ). These hashed class names frequently changed during server updates, causing themes to break unexpectedly. This was a primary source of frustration for theme developers in 2021, requiring constant maintenance.
: In late 2021, projects like IRIDIUM (by Cheesegeezer ) began development to bring back the beloved Windows Media Center look to the Emby interface. How to Apply These Themes emby css themes 2021