Not getting folder thumbnails

[JuiceWSA]

A Movie Library/ <---aim Plex library here - and nowhere else.
...A Movie (YEAR)/ <---not required, but HIGHLY RECOMMENDED!
......A Movie (YEAR).xxx

A TV Show Library/ <---aim Plex Library here - and nowhere else.
.....A TV Show/
.......Season 01/
.........A TV Show - S01E01.xxx

https://support.plex.tv/articles/categories/your-media/

Regarding those bogus embedded Title Fields in your MP4/M4V files:

Video File Naming

With LMA in priority, Embedded Titles within MP4/M4V files are preferred - even over a perfect file name. Local Media Assets should - AT ALL TIMES - remain enabled (unless specifically instructed to turn it off). Local Media Assets should be ‘Demoted’, to the bottom of the stack of active agents under ALL tabs in Shows and Movies, but should NOT be disabled. Local Media Assets is needed for many things - it doesn’t need to be given Tip-Top-Priority (as Plex has so hatefully placed it as it’s …

… and when ‘Refresh Metadata’ doesn’t work after you rename and structure your material:

The Plex Dance ™

The purpose of this is to remove all cached metadata and xml data for an item that Plex usually keeps. This helps when you want to “start from scratch” for particular item move all files for the media item out of the directory your Library is looking at, so Plex will not “see” it anymore scan the library library (to detect changes) empty trash clean bundles (in menu next to server name, when accessed under ‘More’) double check naming schema and move files back scan the library Support articl…

… and Folders never get artwork
We don’t use folders, really…
That’s what we have Plex for.

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