FYI, the Plex LG app has been updated several times this year.
The most recent update 5.84.1, was eight days ago (release notes).
You can verify the version in the Plex app settings or via your list of Authorized Devices.
The app in the LG app store is a bootloader, not the full version of the Plex app. When you launch the app, it checks with hosts at plex.tv and downloads an updated version if one is available.
