It would be a very useful feature is the ability to export your decklist or inventory not just as a .csv file, but also a .txt or .dec file too. I haven't seen this feature on here so I could be missing it but I don't ever use .csv files, mostly .txt but I do know how useful a .csv file can be. So just a feature I'd like to see implemented.

You can do this via the View menu, choosing "Text Card List".