Make a custom filter

[jyfradet]

I have searched a bit but have not found answers to my questions. I would like to have a filter for movies or tv shows to see only watched movies. Right now, we can filter by unwatched. Is it possible for one of the developer to implement it ? Or could anyone point me at how I could customize my filters ? Please note that I am not a programmer. If I can fiddle the installed files without recompiling, that would be great. Let me know if my request is feasible.