Experiencing the ‘Error code: s4002 (Manifest)’ in Plex when streaming live TV via a web browser, but not on media devices, can be indicative of a browser-specific issue. This problem often arises because Plex and the web browser might lack the necessary codec support, especially for MP4 files. This gap in codec support is partly due to FFmpeg, a key multimedia handling tool, having removed the libmp4v2 library due to licensing conflicts. libmp4v2 was originally part of FFmpeg but was excluded because its MPL (Mozilla Public License) was incompatible with FFmpeg’s LGPL (Lesser General Public License), creating legal challenges.

sudo apt-get update && sudo apt-get install ffmpeg libmp4v2-2

sudo dnf install ffmpeg libmp4v2

sudo yum install epel-release && sudo yum install ffmpeg libmp4v2

sudo pacman -Sy ffmpeg libmp4v2

After installing these packages, Plex should handle live TV streaming within your browser (PlexWeb.)