I am going to revisit this because I am seeing the same behavior today (after I renamed some movie files that were erroneously named the same as the movie file (with an index number) and not in an extras subfolder).
To show “evidence” of what I am speaking, and document it.
The screenshots are large but they show what Plex is doing. It seems reluctant to let go of the idea that Extras can also be Parts.
To fix the issue I just move the folder to the Trash, wait for Plex to see the change, then add the folder back.
EDIT:
The issue can be replicated when I lock any of the extras or their containing folder in Finder. I had been doing that because I don’t want FileBot to rename them in the future. This is definitely part of the problem - reproducible.
Screenshot 1
Screenshot 2
This XML file does not appear to have any style information associated with it. The document tree is shown below.
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<Review id="60700" filter="art=60700" tag="Eduardo Guaitsel" text="Anyone who wants to see the best Western needs to admire Cimarron. [Full Review in Spanish]" image="rottentomatoes://image.review.fresh" link="https://archive.org/details/cinemundial16unse/page/292" source="Cine-Mundial"/>
<Review id="3688" filter="art=3688" tag="Mordaunt Hall" text="A graphic and engrossing screen conception." image="rottentomatoes://image.review.fresh" link="https://www.nytimes.com/1931/01/27/archives/the-screen.html" source="New York Times"/>
<Review id="41" filter="art=41" tag="James Berardinelli" text="Critically lauded at the time of its release, Cimarron was beloved by most who saw it. Eight decades later, it is frequently cited on lists of the most undeserving Academy Award winners." image="rottentomatoes://image.review.rotten" link="http://www.reelviews.net/php_review_template.php?identifier=1905" source="ReelViews"/>
<Review id="3687" filter="art=3687" tag="Irene Thirer" text=""Cimarron" is magnificent in scope, powerful in treatment, admirable in acting. But it is even more than all this. It is one of few talking picture productions which inspires rather than awes." image="rottentomatoes://image.review.fresh" link="http://www.nydailynews.com/entertainment/oscars/cimarron-offers-terrifc-thrills-moment-article-1.2088389" source="New York Daily News"/>
<Review id="3619" filter="art=3619" tag="TIME Staff" text="It is a long, full-bodied picture, paced so deftly that although it covers more than half a century of crowded, changing events, it never drags and is rarely jerky." image="rottentomatoes://image.review.fresh" link="http://www.time.com/time/magazine/article/0,9171,740956-3,00.html" source="TIME Magazine"/>
<Review id="3686" filter="art=3686" tag="SMH Staff" text="The conclusion of the story... is not in the least convincing." image="rottentomatoes://image.review.rotten" link="http://nla.gov.au/nla.news-article16782181" source="Sydney Morning Herald"/>
<Review id="660" filter="art=660" tag="Tim Brayton" text="The all-time worst winner of the Academy Award for Best Picture." image="rottentomatoes://image.review.rotten" link="https://www.alternateending.com/2020/01/cimarron-1931.html" source="Alternate Ending"/>
<Review id="3690" filter="art=3690" tag="E. de S. Melcher" text="With due regards to the author's craftsmanship, the picture version seems better than the original." image="rottentomatoes://image.review.fresh" link="https://chroniclingamerica.loc.gov/lccn/sn83045462/1931-02-14/ed-1/seq-3/" source="Washington Star"/>
<Review id="60701" filter="art=60701" tag="H.M." text="It is impossible, of course, in a short notice to give any real idea of so full and detailed a picture -- but Cimarron is emphatically a film which everyone looking for a good entertainment should see." image="rottentomatoes://image.review.fresh" link="http://archive.spectator.co.uk/article/28th-march-1931/11/the-cinema" source="The Spectator"/>
<Review id="3692" filter="art=3692" tag="Witney Seibold" text="I can see the epic tragic scope that Cimarron was going for, and I can glean the dramatic irony inherent in the hugeness of it all, but it just doesn't work. It's a stiff, unengaging movie." image="rottentomatoes://image.review.rotten" link="http://www.nerdist.com/2014/03/best-picture-cimarron-19301931/" source="Nerdist"/>
<Review id="6115" filter="art=6115" tag="Christopher Null" text="Too bad the rest of the film doesn't measure up to the opening." image="rottentomatoes://image.review.rotten" link="http://www.contactmusic.net/film/review/cimarron" source="Filmcritic.com"/>
<Review id="191" filter="art=191" tag="Dennis Schwartz" text="The first western to win an Oscar for Best Picture." image="rottentomatoes://image.review.fresh" link="http://www.sover.net/~ozus/cimarron1931.htm" source="Dennis Schwartz Movie Reviews"/>
<Review id="1243" filter="art=1243" tag="Matt Brunson" text="As a motion picture, this is fairly worthless, crippled by static direction, overblown performances and dull conflicts. But as a study of the American mindset at the time of both the story's setting and the film's production, it's a fascinating look back." image="rottentomatoes://image.review.rotten" link="https://clclt.com/charlotte/view-from-the-couch/Content?oid=2359205" source="Creative Loafing"/>
<Review id="3322" filter="art=3322" tag="Wesley Lovell" text="Consistently dull, this old western tale is highlighted by an endearing debut performance by Irene Dunne." image="rottentomatoes://image.review.fresh" link="http://www.cinemasight.com/Reviews/Annual/1931/Cimarron.html" source="Cinema Sight"/>
<Review id="27029" filter="art=27029" tag="MaryAnn Johanson" text="Get past the occasionally dated feel of Cimarron and you'll find a cracking yarn, one that does eventually make up for itself." image="rottentomatoes://image.review.fresh" link="http://www.flickfilosopher.com/oscars/bestpix/cimarron.shtml" source="Flick Filosopher"/>
<Review id="1246" filter="art=1246" tag="Emanuel Levy" text="Cimarron, a rather weak film, is one of the few Westerns to win the Best Picture Oscar." image="rottentomatoes://image.review.rotten" link="http://www.emanuellevy.com/review/cimarron-1930-1931-6/" source="EmanuelLevy.Com"/>
<Review id="1710" filter="art=1710" tag="Ken Hanke" text="There's a reason Wesley Ruggles' movies aren't often revived and this is one of them." image="rottentomatoes://image.review.fresh" source="Mountain Xpress (Asheville, NC)"/>
<Review id="26350" filter="art=26350" tag="TV Guide Staff" text="It holds up surprisingly well today." image="rottentomatoes://image.review.fresh" link="http://www.tvguide.com/movies/cimarron-110896/review/" source="TV Guide"/>
<Review id="84107" filter="art=84107" tag="Mike Massie" text="Despite Yancey's admirable causes, the pacing is slow and the narrative uninspired, resulting in an important yet ponderous extravaganza." image="rottentomatoes://image.review.rotten" link="http://gonewiththetwins.com/new/cimarron-1931/" source="Gone With The Twins"/>
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