Update readme

Author: nicknsy

README.md

@@ -29,6 +29,8 @@ Jellyscrub [<b>SSL, Cloudflare Proxy</b>] (Default 10s Interval, 320px width):
 <img src="https://github.com/nicknsy/jellyscrub/raw/main/logo/jellyscrub-cloudflare.gif" width="500">
 
 ## Installation ##
+<b>NOTE: If the script is unable to inject due to a lack of permission, this is likely due to the docker container being run as a non-root user while being built as a root user, causing the web files to be owned by root. To solve this, you can remove any lines like `User: 1000:1000`, `GUID:`, `PID:`, etc. from the jellyfin docker compose file. Alternatively, the script can manually be added to the index as described below.</b>
+
 1. Add https://github.com/nicknsy/jellyscrub/blob/main/manifest.json as a Jellyfin plugin repository
 2. Install Jellyscrub from the repository
 3. Restart the Jellyfin server