Merges content from two identical subtitle files in different languages.
This is useful when you are learning a new language.
I watch the film in the language that I am learning with the subtitles in that language, but since I don't yet fully understand them, I also include the translation at the bottom, so that I don't have to go to the translate app every single time.
The translation can be produced using this https://www.syedgakbar.com/projects/dst or similar software.