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There has been a consistent problem with downloading videos from youtube using
The filename has random characters at the end.
e.g, original filename of the video is
Scala Monads: Declutter Your Code With Monadic Design
but the filename of video after downloading is
Monads - Declutter Your Code With Monadic Design-Mw_Jnn_Y5iA.f136.mp4
here is the warning during download:
WARNING: Requested formats are incompatible for merge and will be merged into mkv.
it will be really helpful if somebody could suggest a solution.