I just updated a few days ago to MacOS Beta 10.13.4 Beta (17E139j). Now when launching the Web app and try to watch a movie or TV show on my iMac, the player stop completely and either lets me just hit Play again, or actually resets the show back to the beginning. There are no errors, nor do I find any error logs. Safari version is 11.1 (13605.1.23.1) and the Plex Server version is 18.104.22.16802. Web player is Version 3.27.1. Previous to the update, I was on a previous version of the Beta and had no issues at all.
Same here. DVR only records 2-3 minutes as well before stopping. I can’t find any errors in the log. The web app seems to work fine in Chrome though.