Playlist doesn't show the content of playlist.xml in UI

[TwizzyDizzy]

Describe the bug
If I navigate to a playlist in the UI it doesn't show the content that is actually listed in the playlist.xml file on disk.

To Reproduce
I don't yet know how to reproduce. It used to work yesterday, it does not today.

EDIT 1: with the current state of affairs, it also happens when creating a new playlist. With the same track shown in the screenshot which is not the track I added

Expected behavior
Show the correct tracks in the playlist

Logs

root@pi:/var/lib/jellyfin/data/playlists# pwd
/var/lib/jellyfin/data/playlists
root@pi:/var/lib/jellyfin/data/playlists# find
.
./sunday-joint-interludes [playlist]
./sunday-joint-interludes [playlist]/playlist.xml
./sunday-joint [playlist]
./sunday-joint [playlist]/playlist.xml

Content of playlist.xml:

<U+FEFF><?xml version="1.0" encoding="utf-8" standalone="yes"?>
<Item>
  <Added>3/12/19 1:02:40 AM</Added>
  <LockData>false</LockData>
  <LocalTitle>sunday-joint</LocalTitle>
  <RunningTime>0</RunningTime>
  <PlaylistItems>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Various Artists - JFX Bits #6/06 - Midnight Ravers - Le Triomphe du chaos - part 3.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Various Artists - JFX Bits #6/13 - Matt Elliot - Get Wrecked.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Various Artists - JFX Bits #3/Various Artists - JFX Bits #3/16 - Von Magnet - Mostar Angels.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Various Artists - JFX Bits #3/Various Artists - JFX Bits #3/17 - Professor Psygrooves - 24_7.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Various Artists - JFX Bits #3/Various Artists - JFX Bits #3/18 - Josef Bilek Experience - New Genesis.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Various Artists - JFX Bits #5/03 - Ben Sharpa &amp; Pure Solid - Quarantine.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Degiheugi - Endless Smile/Degiheugi - Endless Smile/01 - Qu'attendez-vous de moi?.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Degiheugi - Endless Smile/Degiheugi - Endless Smile/06 - My Chevrolet Byscayne.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Degiheugi - Endless Smile/Degiheugi - Endless Smile/08 - Psychoanalisis.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Degiheugi - Endless Smile/Degiheugi - Endless Smile/12 - I've got an opportunity.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Degiheugi - Endless Smile/Degiheugi - Endless Smile/16 - Une nuit avec elle.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Mounika. - How Are You?/Mounika. - How Are You/02 - De Roses Et De Colombes.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Mounika. - How Are You?/Mounika. - How Are You/03 - Cut My Hair (feat. Cavetown).mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Mounika. - How Are You?/Mounika. - How Are You/09 - Car Sans Toi Je M'ennuie.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Mounika. - How Are You?/Mounika. - How Are You/11 - Love You Sweet It's What I Do.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Mounika. - How Are You?/Mounika. - How Are You/15 - Outro (Love Makes Problems Disappear).mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Jean du Voyage - The Closest EP/Jean du Voyage - The Closest EP/01 - Good morning.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/Jean du Voyage - The Closest EP/Jean du Voyage - The Closest EP/05 - Hearts feat. Pierre Harmegnies.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/ProleteR - Tribute to the Masters Vol. 1/ProleteR - Tribute to the Masters Vol. 1/01 - Frank Sinatra - That's life (ProleteR tribute).mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/ProleteR - Tribute to the Masters Vol. 1/ProleteR - Tribute to the Masters Vol. 1/02 - Sam Cooke - Having a party (ProleteR tribute).mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/ProleteR - Tribute to the Masters Vol. 1/ProleteR - Tribute to the Masters Vol. 1/06 - Ella Fitzgerald - Basin Street Blues (ProleteR tribute).mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/ProleteR - Rookie EP/ProleteR - Rookie EP/02 - No Place I Can Go.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/HQ-Downloads/ProleteR - Rookie EP/ProleteR - Rookie EP/03 - Not Afraid.mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/Tracks/Carey Bell - Hard working woman (Jack Frost Master).mp3</Path>
    </PlaylistItem>
    <PlaylistItem>
      <Path>/media/ssd/Tracks/Pragmatic Theory - Poldoore - In Your Head.mp3</Path>
    </PlaylistItem>
  </PlaylistItems>
  <Shares>
    <Share>
      <UserId>2e28e6d0cc5b4d0e915bbe914b49c4dc</UserId>
      <CanEdit>true</CanEdit>
    </Share>
  </Shares>
  <PlaylistMediaType>Audio</PlaylistMediaType>
</Item>

Screenshots

System (please complete the following information):

• OS: Raspbian (Debian 9, Linux Hostname 4.19.27-v7+ #1206 SMP Wed Mar 6 14:40:18 GMT 2019 armv7l GNU/Linux)
• Browser: Chrome and Firefox
• Jellyfin Version: 10.2.2

Additional context

[TwizzyDizzy]

Closing this for the time being, as I first have to rule out my reverse-proxying setup to be the cause of this issue. For details, see: #1228 (comment)

Cheers
Thomas