Can confirm, latest update broke LG TV plex app.
It would connect to plex fine, let me browse all the items, when I click play, it would just hang there. Loading bar would not even be animated. Plex server status actually shows that video was attempted to play, but I see no errors other than:
The video did not start playing in time
Works fine on my laptop, though.
Downgraded Plex server to 1.12.1.4885-1046ba85f and even 1.12.0.4829-6de959918, but plex LG client still won't work.
All I see in plex logs is:
Apr 11, 2018 20:34:52.204 [0x14c4937e9700] DEBUG - Beginning read from two-way stream.
Apr 11, 2018 20:34:59.569 [0x14c49cfff700] DEBUG - handleStreamRead code 335544539: short read
edit: more logs
Apr 11, 2018 20:46:21.189 [0x14c493fef700] DEBUG - Request: [XXX.XXX.XXX.XXX:50000 (Subnet)] GET /:/timeline?hasMDE=1&ratingKey=6047&key=%2Flibrary%2Fmetadata%2F6047&state=stopped&playQueueItemID=14745&time=0&duration=1262640 (7 live) GZIP Signed-in Token (XXX)
Apr 11, 2018 20:46:21.190 [0x14c493fef700] DEBUG - Client [XXX] reporting timeline state stopped, progress of 0/1262640ms for guid=, ratingKey=6047 url=, key=/library/metadata/6047, containerKey=, metadataId=6047
Apr 11, 2018 20:46:21.194 [0x14c493fef700] DEBUG - [Now] User is XXX (ID: 1)
Apr 11, 2018 20:46:21.194 [0x14c493fef700] DEBUG - [Now] Device is webOS ().
Apr 11, 2018 20:46:21.195 [0x14c493fef700] ERROR - Unable to find client profile for device; platform=webOS, platformVersion=3.7.0, device=, model=43UJ634V-ZD
Apr 11, 2018 20:46:21.195 [0x14c493fef700] DEBUG - [Now] Updated play state for /library/metadata/6047.
Apr 11, 2018 20:46:21.195 [0x14c493fef700] DEBUG - Statistics: (XXX) Reporting active playback in state 3 of type 4 (scrobble: 0) for account 1
Apr 11, 2018 20:46:21.196 [0x14c493fef700] DEBUG - Streaming Resource: Terminated session 0x14c49b2a62a0:8ohi12w895krcnmiq3k1d4uo with reason Client stopped playback.
Apr 11, 2018 20:46:21.196 [0x14c493fef700] DEBUG - Streaming Resource: Removing session 0x14c49b2a62a0:8ohi12w895krcnmiq3k1d4uo
Apr 11, 2018 20:46:21.197 [0x14c49cdfe700] DEBUG - Completed: [XXX.XXX.XXX.XXX:50000] 200 GET /:/timeline?hasMDE=1&ratingKey=6047&key=%2Flibrary%2Fmetadata%2F6047&state=stopped&playQueueItemID=14745&time=0&duration=1262640 (6 live) GZIP 8ms 538 bytes (pipelined: 2)
handleStreamRead code 2: End of file
Edit2: Uninstalling and reinstalling Plex TV app did not work
Installed XPlay from LG app store and that one works fine with latest Plex server update.
Pretty much confirms the problem is not with unraid or plex container, but with LG app.
Will just buy XPlay license (about seven fiddy EUR) and stick with that as a client, it's miles ahead of official app anyway.