Hi,

I have just made an experiment with a self made mkv. It was created using mkvtoolnix-gui. For testing I have added the following subtitles:

Text #1
ID                                       : 4
Format                                   : UTF-8
Codec ID                                 : S_TEXT/UTF8
Codec ID/Info                            : UTF-8 Plain Text
Duration                                 : 45 min 17 s
Bit rate                                 : 297 b/s
Count of elements                        : 2289
Stream size                              : 98.8 KiB (0%)
Language                                 : English
Default                                  : Yes
Forced                                   : No

Text #2
ID                                       : 5
Format                                   : S_TEXT/WEBVTT
Codec ID                                 : S_TEXT/WEBVTT
Duration                                 : 45 min 17 s
Bit rate                                 : 829 b/s
Count of elements                        : 2365
Stream size                              : 275 KiB (0%)
Language                                 : English
Default                                  : No
Forced                                   : No

What surprised me that while mediainfo seemingly recognizes the second VTT subtitle format, if I add the media file to Plex, the SRT gets correctly recognized though the VTT version is displayed as None. In the XML I can see that the codec is indeed none. So it doesn't seem to be recognized. And of course it crashes my web player completely.

Is there anything I can do about this? I have a powerful enough server to transcode and burn in those subs if needed. I just want Plex to support VTT.

Thanks