Subtitles... inside of chapters? Can I extract?

[VideoBeginner]

Using MKVToolNix, I see that my m4v file has a chapter track and no subtitle tracks even though subtitles are available when playing in VLC. Removing the chapter track removes the subtitles. (I did not even know that you could place subtitles there.)

Is there a way to extract the subtitles and separate them from the chapter data? I want to convert them (probably to SRT) and reinsert without chapters.

[Nikse555]

You could try mp4box - https://gpac.wp.mines-telecom.fr/mp4box/

You can use the command line:
MP4Box -info video.m4v
and
MP4Box -srt <trackId> video.m4v

[VideoBeginner]

Thanks. I will give that a try.