For playlists, file extensions .m3u and m3u8 can work with lists consisting of only file paths, without any other information.
And those playlists will work on any audio or video player I can think of.
I'd be happy with only support for .m3u/.m3u8 playlists..
But, in case is of interest, I include playlist examples:
{{{ .M3U / .M3U8 — Audio/Video Playlists for most players (even without the #EXTM3U/#EXTM3U8 header) }}} ☆
#EXTM3U
D:\Music\Jovian\Bon Jovi [1995] These Days\01. Hey God.mp3
D:\Music\Jovian\Bon Jovi [1995] These Days\02. Something For The Pain.mp3
D:\Music\Jovian\Bon Jovi [1995] These Days\03. This Ain't A Love Song.mp3
D:\Music\Jovian\Bon Jovi [1995] These Days\04. These Days.mp3
D:\Music\Jovian\Bon Jovi [1995] These Days\05. Lie To Me.mp3
D:\Music\Jovian\Bon Jovi [1995] These Days\06. Damned.mp3
{{{ .PLS — Basically an INI file }}}
[playlist]
File1=D:\mdnava\OneDrive\Music\Jazz\John Coltrane [1961] My Favorite Things\01. My Favorite Things.mp3
File2=D:\Music\Jazz\John Coltrane [1961] My Favorite Things\02. Everytime We Say Goodbye.mp3
File3=D:\Music\Jazz\John Coltrane [1961] My Favorite Things\03. Summertime.mp3
File4=D:\Music\Jazz\John Coltrane [1961] My Favorite Things\04. But Not For Me.mp3
File5=D:\Music\Jazz\John Coltrane [1961] My Favorite Things\05. My Favorite Things, Pt. 1 [Single Version][Version].mp3
{{{ .MPCPL — Media Player Classic / Supports remembering playback times }}}
MPCPLAYLIST
audio,-1
subtitles,-1
1,type,0
1,time,00:03:27
1,filename,E:\Videos\Deutsche\Yvonne Catterfeld - Pendel.mp4
2,type,0
2,time,00:03:53
2,filename,E:\Videos\Deutsche\Silbermond - Leichtes Gepäck (Offizielles Musikvideo).mp4
3,type,0
3,time,00:03:13
3,filename,E:\Videos\Deutsche\Silbermond - Durch die Nacht.mp4
4,type,0
4,time,00:05:11
4,selected,1
4,filename,E:\Videos\Deutsche\Lotte & Max Giesinger - Auf das, was da noch kommt (Official Video).mp4
5,type,0
5,time,00:03:31
5,filename,E:\Videos\Deutsche\Lotte - Auf beiden Beinen.mp4
{{{ .DPL — PotPlayer / Supports remembering playback times }}}
DAUMPLAYLIST
playname=E:\Videos\Française\Zaz performs 'Je Veux' LIVE.mp4
playtime=53229
topindex=0
saveplaypos=0
1*file*E:\Videos\Française\ZAZ - Je veux street live.mp4
1*duration2*240814
1*start*89343
2*file*E:\Videos\Française\Zaz - La Fée (Live - C'Cauet sur NRJ).mp4
2*duration2*240767
2*start*52114
3*file*E:\Videos\Française\Zaz - On ira (Street Live).mp4
3*duration2*178816
3*start*28800
4*file*E:\Videos\Française\Zaz à Montmartre - Les passants (Street Live).mp4
4*duration2*260620
4*start*31233
5*file*E:\Videos\Française\Zaz performs 'Je Veux' LIVE.mp4
5*duration2*202895
5*start*53229
I do think adding support for playlists other than M3U/M3U8 would make the File List Editor go beyond its intended scope.
(I think support for M3U/M3U8 would only require not to add any missing EFU CSV headers and fields when editing)
You know, and I must say, the File List Editor would make a hell of a fine CSV editor on its own.
But I do understand is not its purpose. Just saying..
Best regards!