I'm facing a little problem regarding the combination of subtitle tracks in MKV files (Don't even know if this is possible... Therefore I ask).

I could not find anything useful on this using search function and google.

So the problem:

I've got two subtitle files (let's call them de.ass and de-notes.ass) now I want de.ass to be a subtitle track - That's easy.

The problem itself consists of the combination of both files for track two... I want to only mux de.ass once and turn on de-notes.ass (containing optional translation notes) only if track 2 is activated so track two would mean "show track 1 and de-notes.ass".

Files:

de.ass
de-notes.ass

Tracks:

1 - Language: de - Name: German - de.ass
2 - Language: de - Name: German with Notes - Track 1 + de-notes.ass

This would reduce maintenance if I update the dialogue script (de.ass) since I would only need to replace track one's ass file.

So is this possible? And if yes, how?

Thanks for your help in advance.