There's no need to pay for Autobookmark or Evermap if you just need to sort your bookmarks alphabetically.

Below is a simple command to shrink an mkv file using ffmpeg -- i.e., convert mkv to mkv -- and keep all existing subtitles and audio tracks (which is NOT ffmpeg's default). You can use this overnight to shrink 25 GB MKV files to around 5 GB or so -- i.e., 80% smaller.

Preview (to test the results):

Full video:

Explanation

The following shows a working script with explanatory comments and Wikipedia illustration below to internationalize / i18n bash shell scripts on CentOS 7.4:

The DockerFile instruction VOLUME [ "/data" ] creates an anonymous volume mounted as /data that allows just 1 container to use it (unless you issue a docker run --volumes-from or bind mount it with docker run -v /var/lib/docker/volumes/9283:/data) until you docker rm that container. After docker rm, the volume remains but it's inaccessible by containers without a bind mount.

I've been working on basic Algebra II concepts recently, especially tree diagrams for combinations and permutations. Permutations are relatively straightforward, but not combinations. So, I asked a question on Math.StackExchange.com, and although I never received a response, I think that my sketch, shown below, is roughly accurate:

Enter Unicode characters using AutoHotKey (AHK)

1. Download AutoHotKey (free)

For a long time, I had been curious what an IPA to speech sounds / MP3 audio converter would sound like. Google doesn't list any free tools. So today, I wrote a free converter in Python. The code is extremely basic and not a good example of programming, but it does illustrate the point of why so few converters probably exist: the results are nearly worthless--at least, when using such simple logic (i.e., just play each IPA sound in order as transcribed).