Agadxwad5d4jvg.mkv -

: If you need to keep embedded subtitles for editing, ensure your destination format (like MP4) is set to "Burn-in" or "Render" the subtitles if "Copy" isn't supported by your editor.

: If your computer lags during editing, use Handbrake to transcode the file into a more "edit-friendly" codec like ProRes or H.264. AgADXwAD5d4JVg.mkv

: If the MKV won't open, use MKVToolNix to "Multiplex" it into a new MKV file, which rebuilds the container header and fixes internal errors. : If you need to keep embedded subtitles