My guide to easily fixing split MKVs using MKVToolsNix GUI.

It's just not worth having guaranteed frustrations and likely problems for the sake of an insignificant reduction in size.

Those who are on a tight storage/data budget will be going for the ultra compressed files where the saving is even more insignificant.

Who cares about bandwidth: Certainly not the people that are downloading these already bloated BD releases.Storage is cheap: Seriously, HDDs these days come in large capacities at reasonable prices - the extra clutter and frustration is way worse than an extra drop in the bucket on disk usage.Less internet bandwidth: If it uses less space to store, it will also transfer less data downloading it.Less disk space: The OP/ED is only stored in one video file and reused several times instead of repeating the same data in each episode.You're forced to accept extra clutter in your folders and extra (unwanted) entries in your media library. If you're hoping to tidy up by putting them in a sub-folder, it will break and your episodes will be missing the OP/ED. Cluttered Folders: The OP/ED files must be kept in the same folder as the episode.Maybe you'll want to put it on your media server or your phone and it just won't work right there.

While support for this anti-feature has improved recently, it still won't work everywhere.

It does not work with all media players: This will cause the OP/ED to be excluded from the episode and not played.

The OP/ED files are not included in the episode video, but instead as separate files that your media player is supposed to find and insert.

As I will get into below, this is a problem that requires fixing. Sometimes I end up downloading an anime series from a sadistic fansubber / release group who felt the need to remove the OPs and EDs from the episode video files and store them as separate files, linking them in as chapter references in hopes that your media player will somehow find them and put them back in. Since I have found and documented the solution myself, this post has been rewritten as an informational post to help others in need. Note: This was originally a post asking for a solution to this annoying problem.

Mkvtoolnix gui split by chapter