Extract the subtitle from track 3 of a specific file

Merge and extract multimedia streams.
More information: <https://mkvtoolnix.download/doc/mkvmerge.html>.
Trick copyright: tl;dr; <https://github.com/tldr-pages/tldr>

mkvextract tracks {{path/to/file.mkv}} {{3}}:{{path/to/subs.srt}}

click the source code to copy install mkvmerge on any operating system with command-not-found.com